• Archives of Plastic Surgery
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• v.42 no.4
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• pp.461-468
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• 2015

Background Functional restoration of the facial expression is necessary after facial nerve resection to treat head and neck tumors. This study was conducted to evaluate the functional outcomes of patients who underwent facial nerve cable grafting immediately after tumor resection. Methods Patients who underwent cable grafting from April 2007 to August 2011 were reviewed, in which a harvested branch of the sural nerve was grafted onto each facial nerve division. Twelve patients underwent facial nerve cable grafting after radical parotidectomy, total parotidectomy, or schwannoma resection, and the functional facial expression of each patient was evaluated using the Facial Nerve Grading Scale 2.0. The results were analyzed according to patient age, follow-up duration, and the use of postoperative radiation therapy. Results Among the 12 patients who were evaluated, the mean follow-up duration was 21.8 months, the mean age at the time of surgery was 42.8 years, and the mean facial expression score was 14.6 points, indicating moderate dysfunction. Facial expression scores were not influenced by age at the time of surgery, follow-up duration, or the use of postoperative radiation therapy. Conclusions The results of this study indicate that facial nerve cable grafting using the sural nerve can restore facial expression. Although patients were provided with appropriate treatment, the survival rate for salivary gland cancer was poor. We conclude that immediate facial nerve reconstruction is a worthwhile procedure that improves quality of life by allowing the recovery of facial expression, even in patients who are older or may require radiation therapy.

• Nuclear Engineering and Technology
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• v.5 no.2
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• pp.103-114
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• 1973

Radiation grafting of acrylic acid and 4-vinylpyridine at room temperature has been studied by an impregnation method to improve the hygroscopic properties, the antistatic behavior and the dyeability of polyester fabric. Polyester fabric was impregnated with acrylic acid or aqueous emulsion of acrylic acid-4-vinylpyridine by immersion at 25$^{\circ}$or 7$0^{\circ}C$. The impregnated fabric was irradiated under nitrogen gas with ${\gamma}$-rays from Co-60. When acrylic acid grafted polyester fabric was treated with sodium carbonate, calcium acetate and potassium persulfate, tne rate of water absorption was increased and most parts of polyacrylic acid formed were extracted off from the fabric with 0.1% solution of sodium hydroxide at 10$0^{\circ}C$. In the case of the impregnation of a mixture of acrylic acid and 4-vinylpyridine the petcent of grafting has been shown to be proportional to the ratio of 4-VP/AA and radiation dost. Estimating by contact angle measurements of water on the various polymer surfaces, the antistatic behavior was decreased with the increase of grafting percent. The investigation of electron micrograph disclosed the existence of certain type of discontinuities in the acrylic acid grafted polyester fiber which was treated with various salts.

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.954-959
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• 1999

Radiation-induced grafting of 2-hydroxyethyl methacrylate(HEMA), acrylic acid(AAc) and methacrylic acid(MAAc) onto polypropylene microfiltration membrane has been studied. The effect of grafting conditions such as solvent composition(MeOH and $H_2O$) and monomer concentration on the grafting yield in investigated. The highest degree of grafting is obtained at a solvent composition of 25% $H_2O$:75% MeOH for HEMA, pure water for AAc and 50% $H_2O$:50% MeOH for MAAc. Modification of the PP membranes with hydrophilic monomers is shown to cause an increase in the water permeation flux of the membranes. It is found that HEMA is the best monomer to increase the water permeation flux and the highest water permeation flux is obtained at 99% degree of grafting. The water permeation flux of AAc-grafted PP membrane and MAAc-grafted PP membrane is very sensitive to environmental pH and $Cu^{2+}$ ion, but the water permeation flux of HEMA-grafted PP membrane scarcely depends on pH and $Cu^{2+}$ ion.

• Applied Chemistry for Engineering
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• v.17 no.3
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• pp.303-309
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• 2006

In this study, functional anion-exchange membranes have been prepared and characterized to improve the permeation fluxes of the anion and urea for peritoneum dialysis. They were prepared by UV and radiation graft polymerization methods. The separation-membrane prepared by UV graft polymerization showed the highest grafting degree when HEMA and VBTAC were mixed by 1:2 ratio. However, the grafting degree decreased slightly at compositions above the 1:2 ratio because of the disruption of UV penetration caused by build-up of homopolymer. In the case of photo-initiator, the grafting degree increased up to 0.2 wt%, above which it decreased to a small extent. For the two membranes prepared by radiation graft polymerization, the VBTAC/HEMA membrane showed 96% grafting degree for 6 h reaction time and the GMA membrane showed over 100% grafting degree for 2 h reaction time. Anion-exchange membranes were prepared with 113% grafting degree and with DEA and TEA exchange groups. The DEA membrane showed the conversion degree of 70% in 4 h reaction time while the TEA membrane showed 30% in 2 h reaction time. The prepared anion-exchange membranes were permeable to only anions and urea, but not cations.

• Journal of Radiation Industry
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• v.5 no.4
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• pp.365-370
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• 2011

Electrospun nanofibers prepared with synthetic biodegradable polymer have some limitations in regulating adhesion, proliferation, and spreading of cells because of their surface hydrophobicity and absence of cell-interaction. In this study, we functionalized the electrospun poly(L-lactide-co-${\varepsilon}$-caprolactone) (PLCL) nanofibers with acrylic acid (AAc) to modulate their surface hydrophilicity using electron-beam irradiation method and then measured grafting ratio of AAc, water contact angle, and ATR-FTIR of AAc-grafted nanofibers. A grafting ratio of AAc on the nanofibers was increased as irradiation dose and AAc concentration were increased. AAc-grafted nanofibers also have higher wettability than non-modified nanofibers. In conclusion, those surface-modified nanofibers may be an essential candidate to regulate cell attachment in tissue engineering applications.

• Nuclear Engineering and Technology
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• v.9 no.2
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• pp.65-74
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• 1977

The radiation-induced graft polymerization of acrylic acid onto polyester fabric was investigated with accelerated electron beams as ratiation source at high dose rates. Homopolymerization was suppressed by addition of cations which is known as homopolymerization inhibitor, but this practical advantage was obtained at the expense of grafting efficiency. The rate of grafting (%/sec) was proportional to the 0.82th power of dose rates over the range from 1.6$\times$10$^{6}$ to 10$\times$10$^{6}$ rad/sec. The grafted polyester fabric showed considerable improvement in moisture regain and antistatic properties.

• Journal of the Korean Electrochemical Society
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• v.12 no.2
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• pp.173-180
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• 2009

In order to develop a novel polymer electrolyte membrane for direct methanol fuel cell (DMFC), styrene monomer was graft-polymerized into poly(tetrafluoroethylene perfluoropropyl vinyl ether) (PFA) film followed by a sulfonation reaction. The graft polymerization was prepared by the $\Upsilon$-ray radiation-grafting method. Subsequently, sulfonation of the radiation-grafted film was carried out in a chlorosulfonic acid/1,2-dichloroethane (2 v/v%) solution. The chemical, physical, electrochemical and morphological properties of the radiation-grafted membranes (PFA-g-PSSA) were characterized by fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The water uptake, ionic conductivity, and methanol permeability of the PFA-g-PSSA membrane were also measured. The cell performances of MEA prepared with the PFA-g-PSSA membranes were evaluated and the cell resistances were measured by an impedance analyzer. The MEA using PFA-g-PSSA membranes showed superior performance for DMFCs in comparison with the commercial Nafion 112 membrane.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.05a
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• pp.123-123
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• 1998

• Nuclear Engineering and Technology
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• v.10 no.4
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• pp.195-201
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• 1978

The radiation-induced graft polymerization of methacrlic acid and methyl methacrylate onto a polyester fabric was investigated with ${\gamma}$-ray as the radiation source, and the rate of grafting was examined. When acrylic acid, methacrylic acid, and methyl methacrylate were grafted onto a polyester fabric, grafting efficiency was depened upon the dielectric constant of the solvent in the monomer mixture. The yield of the graft polymerization was related to the total dose, the concentration of the monomer, and the concentration of the swelling agent. The melting point and the glass transition temperature of MA and MMA grafted copolymers were analysed by means of DTA. Physical properties, such as the moisture regain, the antistatic property, and the wicking time were measured.

• Macromolecular Research
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• v.11 no.5
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• pp.347-351
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• 2003

The hydrophobic ligand-containing hollow polypropylene (PP) membranes were synthesized by the mutual radiation induced graft copolymerization with glycidylmethacrylate (GMA) onto hollow PP membrane followed by the subsequent functionalization with L-phenylalanine. FT-IR, elemental analysis and UV spectroscopy were utilized to characterize copolymer composition, and degree of grafting, functionalization conversion and ${\gamma}$-globulins adsorption. The degree of grafting on the PP surface increased with the reaction time and total dose of E-beam. In the subsquent functionalization, the amount of L-phenylalanine increased with the increase in the degree of grafting and the degree of conversion was about 30%. The ${\gamma}$-globulins adsorption experiments showed that adsorption capacity had a maximum value at pH 8. The ${\gamma}$-globulins adsorption capacity in the basic pH region was higher than in the acidic pH region.