• Archives of Reconstructive Microsurgery
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• 제8권1호
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• pp.71-76
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• 1999

Until recently, the cranial base tumors were deemed unresectable due to the inability to diagnose the extent of the involvement accurately and to approach and excise the tumor safely. With refinements in CT and NMR scanning and development of craniofacial techniques, reconstruction becomes absolutely crucial in allowing successful resection of these tumors. Resection of these tumors may sometimes result in massive and complex extirpation defects that are not amendable to local tissue closure. In such cases, the free tissue transfer was a useful alternative because it can provide large amount of well-vascularized tissues and reliable separation of intracranial space from bacterial flora of the upper airway. The microvascular free tissue transfer was used in 9 patients at our center to reconstruct the cranial base defects. Of these, 8 were free rectus muscle flaps, and 1 was free latissimua dorsi muscle flap. There were 1 case of partial flap loss and 1 case of postoperative wound infection. The large, complex defects were successfully reconstructed by one stage operation and the functional and aesthetic results were satisfactory with acceptable complication rates.

• International Journal of Precision Engineering and Manufacturing
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• 제1권1호
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• pp.133-145
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• 2000

Plastic molding designers are frequently faced with optimizing multiple defects in injection molded parts. these defects are usually in conflict with each other, and thus a tradeoff needs to be made reach a final compromised solution. In this study, an automated injection molding design methodology has been developed to optimize multiple defects of injection molded parts. Two features of the proposed methodology are as follows: one is to apply the utility theory to transform the original multiple objective optimization problem into single objective optimization problem with utility as objective function, the other is an implementation of a direct search-based injection molding optimization procedure with automated consideration of process variation. The modified complex method is used as a general optimization tool in this research. The developed methodology was applied to an actual molding design and the results showed that the methodology was useful through the CAE simulation using a commercial injection molding software package. Applied to production, this study will be of immense value to industry in reducing the product development time and enhancing the product quality.

• 대한두개안면성형외과학회지
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• 제24권6호
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• pp.260-265
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• 2023

Background: The traditional nasolabial V-Y advancement flap is widely used for midface reconstruction, particularly for the lower third of the nose and upper lip, as its color and texture are similar to these areas. However, it provides insufficient tissue to cover large defects and cannot restore the nasal convexity, nasal ala, and adjacent tissues. The purpose of this study is to investigate the modified nasolabial V-Y advancement flap with extension limbs the along alar crease for the reconstruction of complex midface defects. Methods: A retrospective analysis of 18 patients, who underwent reconstruction with the modified nasolabial V-Y advancement flap, was performed between September 2014 and December 2022. An extension limb was added along the alar crease, adjacent to the defect area, and was hinged down as a transposition flap at the end of the advancement flap. Results: The extension limb along the alar crease successfully covered large and complicated defects, including those of the ala, the alar rim, the alar base, the nostrils, and the upper lip, with minor complications. Conclusion: The alar crease is a good donor site for the reconstruction of large and complex nasal and upper lip defects.

• Archives of Plastic Surgery
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• 제40권6호
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• pp.748-753
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• 2013

Background Nasal reconstruction is one of the most difficult challenges for the head and neck surgeon, especially in the case of complex full thickness defects following malignant skin tumor resection. Full-thickness defects require demanding multi-step reconstruction. Methods Seven patients underwent surgical reconstruction of full-thickness nasal defects with a bi-pedicled forehead flap shaped appropriately to the defect. Patients were aged between 58 and 86 years, with a mean age of 63.4 years. All of the tumors were excised using traditional surgery, and in 4 of the patients, reconstruction was performed simultaneously following negativity of fresh frozen sections of the margins under general anesthesia. Results Nasal reconstruction was well accepted by all of the patients suffering non-melanoma skin tumors with acceptable cosmetic outcomes. The heart-shaped forehead flap was harvested in cases of subtotal involvement of the nasal pyramid, while smaller defects were reconstructed with a wing-shaped flap. No cartilaginous or osseous support was necessary. Conclusions This bi-pedicled forehead flap was a valid, versatile, and easy-to-implement alternative to microsurgery or multi-step reconstruction. The flap is the best indication for full-thickness nasal defects but can also be indicated for other complex facial defects in the orbital (exenteratio orbitae), zygomatic, and cheek area, for which the availability of a flap equipped with two thick and hairless lobes can be a valuable resource.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제40권
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• pp.7.1-7.5
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• 2018

Background: Oroantral communicating defects, characterized by a connection between the maxillary sinus and the oral cavity, are often induced by tooth extraction, removal of cysts and benign tumors, and resection of malignant tumors. The surgical defect may develop into an oroantral fistula, with resultant patient discomfort and chronic maxillary sinusitis. Small defects may close spontaneously; however, large oroantral defects generally require reconstruction. These large defects can be reconstructed with skin grafts and vascularized free flaps with or without bone graft. However, such surgical techniques are complex and technically difficult. A buccal fat pad is an effective, reliable, and straightforward material for reconstruction. Case presentation: This report describes three cases of reconstruction of large oroantral defects, all of which were covered by a pedicled buccal fat pad. Follow-up photography and radiologic imaging showed successful closure of the oroantral defects. Furthermore, there were no operative site complications, and no patient reported postsurgical discomfort. Conclusion: In conclusion, the use of the pedicled buccal fat pad is a reliable, safe, and successful method for the reconstruction of large oroantral defects.

• Animal cells and systems
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• 제11권2호
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• pp.129-134
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• 2007

The initiation of eukaryotic DNA replication requires assembly of the pre-replicative complex (Pre-RC) through the concerted action of Orc, Cdc6, Cdt1 and Mcm2-7 complex during G1 phase. The pre-RC assembly licenses individual replication origins for the initiation of DNA replication and sufficient number of the pre-RC is essential for proper progression of S phase. However, it is not well known how cells recognize the completion of the pre-RC assembly before G1-S transition. In order to understand the cellular responses to the defects in pre-RC assembly, we depleted the known components of pre-RC proteins using the small interference RNAs in HeLa cells. Although the defects of pre-RC assembly by the depletion of the pre-RC proteins such as Orc2, Cdt1, Mcm2 & Mcm10 did not elicit the activation of Chk1- or Chk2-dependent checkpoint pathways, these cells still showed significant decrease in the cellular level of Cdc25A proteins. These results suggests that a novel checkpoint pathway exist in HeLa cells, which is not dependent upon Chk1 or Chk2 proteins and play essential roles in the cellular responses to the defects in the pre-RC assembly. Also, among those four proteins tested in this study, the depletion of Mcm10 and Cdt1 proteins significantly increased the apoptotic cell death in HeLa cells, suggesting that these proteins not only play roles in the pre-RC assembly, but also are involved in the checkpoint responses to the defects in the pre-RC assembly.

• Archives of Plastic Surgery
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• 제41권5호
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• pp.556-561
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• 2014

Background Groin dissections result in large wounds with exposed femoral vessels requiring soft tissue coverage, and the reconstructive options are diverse. In this study we reviewed our experience with the use of the pedicled anterolateral thigh and vertical rectus abdominis musculocutaneous flaps in the reconstruction of large groin wounds. Methods Groin reconstructions performed over a period of 10 years were evaluated, with a mean follow up of two years. We included all cases with large or complex (involving perineum) defects, which were reconstructed with the pedicled anterolateral thigh musculocutaneous or the vertical rectus abdominis musculocutaneous (VRAM) flaps. Smaller wounds which were covered with skin grafts, locally based flaps and pedicled muscle flaps were excluded. Results Twenty-three reconstructions were performed for large or complex groin defects, utilising the anterolateral thigh (n=10) and the vertical rectus abdominis (n=13) pedicled musculocutaneous flaps. Femoral vein reconstruction with a prosthetic graft was required in one patient, and a combination flap (VRAM and gracilis muscle flap) was performed in another. Satisfactory coverage was achieved in all cases without major complications. No free flaps were used in our series. Conclusions The anterolateral thigh and vertical rectus abdominis pedicled musculocutaneous flaps yielded consistent results with little morbidity in the reconstruction of large and complex groin defects. A combination of flaps can be used in cases requiring extensive cover.

• 인간식물환경학회지
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• 제23권3호
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• pp.347-362
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• 2020

Background and objective: It is difficult to conclusively determine the exact cause of tree defects since multiple causes are involved such as climate change, plantation, tree quality and planting time, construction, planting base, drainage, sunshine conditions, maintenance, and microclimate. The data related to landscaping construction defects are scattered or fragmented by companies and years, but not managed systematically by the defect information management system. Most of the earlier studies associated with tree defects in apartment complexes suggested defect rates after examining tree defects in the completed construction site and proposed fragmentary and subjective conclusions about the causes of defects observed in trees with high defect rates. It is proposed to continue to conduct studies on the establishment and analysis of systematic databases to identify the exact causes of tree defects and measures to improve, and the need to accumulate systematic data in the construction process where many defects arises. This study was conducted to reduce the defects of trees planted in apartment complexes. Methods: Main factors related to tree defects were subdivided based on the results of literature review and a defect investigation at the completion site, and tree history management items were selected and subdivided during the construction stage. Results: The criteria for the preparation of subdivided items were obtained, and the tree history management checklist was written for the site under actual construction and a systematic database was established. Items that are categorized based to the causes of defects include the location of nurseries, date, tree quality, site conditions, planting techniques, microclimates, and maintenance. Conclusion: This study suggested tree history management items based on the tree defects that can be identified at the construction stage and applied them to the selected study site, which differentiates this study from earlier studies. It will be necessary to conduct a comprehensive and objective time series analysis on tree defects that occur over time by continuously monitoring and collecting data after construction.

• Journal of Chest Surgery
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• 제22권1호
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• pp.95-105
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• 1989

The records of 248 patients over 16 years of age who had undergone a surgical correction of a congenital cardiovascular malformation during the period of 10 years from August, 1978 to July, 1988 were reviewed. During this period, the incidence of congenital cardiovascular malformation in adult was 18.2% of 1376 total heart disease operated on and 25.5% of 986 congenital heart defects. Among them, there were 200 patients in acyanotic group and 48 patients in cyanotic group. Male versus female ratio was 1:1.28. The oldest patient was 59 years old female who had atrial septal defect. The mean age was 24.4 years old. The distribution of the lesions showed a large preponderance of atrial septal defects [37.19o] followed in frequency by ventricular septal defects [918.1%], patent ductus arteriosus [17.3%], tetralogy of Fallot [16.1%], and a variety of other complex malformations[3.2%]. In the pediatric age group, relative frequency was different from that of this adult group, showing ventricular septal defects, tetralogy of Fallot, patent ductus arteriosus and atrial septal defects in order of incidence. The hospital mortality and late mortality were 6.0% and 1.7% respectively. The causes of hospital death were low cardiac output in 10 patients, arrhythmia in 2, air embolism in 1, sepsis in 1 and respiratory failure in l. Clinical improvement upto NYHA functional class I or II postoperatively has been achieved and sustained in all patients following repair except the patients of late death and receiving reoperation. This result confirms that congenital heart defects in the adults can be corrected with a good outcome and an aggressive operative approach seems justified.

• Membrane and Water Treatment
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• 제9권2호
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• pp.105-113
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• 2018

Maillard reaction products like melanoidins present in industrial fermentation wastewaters are complex compounds with various functional properties. In this work, novel ultrafiltration (UF) mixed matrix membrane (MMM) composed of polysulfone (PSF) and nanocomposites was prepared through a phase inversion process for the recovery of melanoidins. Nanocomposites were prepared with acid functionalized multiwalled carbon nanotubes (MWCNTs) as the reinforcing filler for chitosan-thermoplastic starch blend. Higher nanocomposites content in the PSF matrix reduced the membrane permeability and melanoidins retention indicating tighter membrane with surface defects. The membrane surface defects could be sealed with dilute polyvinyl alcohol (PVA) solution. The best performing membrane (1% nanocomposites in 18% PSF membrane sealed with 0.25% PVA coating) resulted in uniform melanoidins retention of 98% and permeability of 3.6 L/m2 h bar over a period of 8h. This demonstrates a low fouling PSF membrane for high melanoidins recovery.