• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제35권5호
• /
• pp.287-293
• /
• 2009

Cell survival is the result of a balance between programmed cell death and cellular proliferation. Cell membrane receptors and their associated signal transducing proteins control these processes. Of the numerous receptors and signaling proteins, epidermal growth factor receptor (EGFR) is one of the most important receptors involved in signaling pathways implicated in the proliferation and survival of cancer cells. EGFR is often highly expressed in human tumors including oral squamous cell carcinomas, and there is increasing evidence that high expression of EGFR is correlated with poor clinical outcome of common human cancers. Therefore, we examined the antiproliferative activity of gefitinib, epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI), in head and neck cancer cell lines. SCC-9, KB cells were cultured and growth inhibition activity of gefitinib was measured with MTT assay. To study influence of gefitinib in cell cycle, we performed cell cycle analysis with flow cytometry. Western blot was done to elucidate the expression of EGFR in cell lines and phosphorylation of EGFR and downstream kinase protein, Erk and Akt. Significant growth inhibition was observed in SCC-9 cells in contrast with KB cells. Also, flow cytometric analysis showed G1 phase arrest only in SCC-9 cells. In Western blot analysis for investigation of EGFR expression and downstream molecule phosphorylation, gefitinib suppressed phosphorylation of EGFR and downstream protein kinase Erk, Akt in SCC-9. However, in EGFR positive KB cells, weak expression of active form of Erk and Akt and no inhibitory activity of phosphorylation in Erk and Akt was observed. The antiproliferative activity of gefitinib was not correlated with EGFR expression and some possibility of phosphorylation of Erk and Akt as a predictive factor of gefitinib response was emerged. Further investigations on more reliable predictive factor indicating gefitinib response are awaited to be useful gefitinib treatment in head and neck cancer patients.

• 대한음성언어의학회:학술대회논문집
• /
• 대한음성언어학회 2017년도 제46차 춘계학술대회
• /
• pp.87-87
• /
• 2017

• 한국결정성장학회지
• /
• 제25권4호
• /
• pp.140-144
• /
• 2015

Tonpilz 트랜스듀서에서 head mass에 영향을 미치는 요소로써 그 형상과 무게 및 소재의 영향을 연구하였다. 형상 요소로는 head mass의 옆면이 대칭 축과 이루는 각도를 그 인자로 하여 0도, 35.5도, 60도로 변화시키면서 대역폭과 출력의 변화를 모사하였다. 그 결과 Al의 경우에는 35.5도에서 대역폭이 최대 값이 되었으며 그 때의 대역폭은 86.4 %로 계산되었다. Head mass의 중량은 대역폭에는 큰 영향이 없이 출력에만 영향을 미치는데 중량이 25 % 감소하였을 때 20 % 정도 출력이 증가하였다. 끝으로 head mass의 소재를 Ti로 변경하였을 때에는 밀도의 차이에 의한 무게의 증가에도 불구하고 출력이 100 % 향상되었는데 이는 Ti의 탄성률 같은 기계적 특성의 영향으로 판단되며 최대의 대역폭을 얻기 위한 형상은 45도에서 얻어졌고 대역폭은 88.1 %이었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제21권8호
• /
• pp.1171-1177
• /
• 2008

The performance of growing rabbits fed Ruzi grass (Brachiaria ruziziensis), head lettuce (Lactuca sativa) residue, Mimosa pigra and water spinach (Ipomoea aquatica) was studied in an experiment using 64 rabbits (4 males and 4 females per treatment) of 2 breeds, New Zealand White and a crossbred between New Zealand White and native breed. The rabbits had an average initial weight of 668 g, were about 6 weeks old and were housed in individual pens. The foliages were fed ad libitum and a commercial concentrate was fed at a restricted level of 2% of body weight on a dry matter (DM) basis. In the digestibility experiment, the rabbits, 4 per foliage and males only, were fed the same foliages as in the growth experiment but without concentrate. Daily weight gain was lower in the group fed Ruzi grass, 14.8 g/d (p<0.001) compared to 17.6, 18.5 and 18.4 g/d for head lettuce, Mimosa pigra and water spinach, respectively. Feed intake and feed conversion ratio were lowest for the rabbits fed water spinach, 66 g DM/d and 3.6 kg DM/kg live weight, respectively. The New Zealand White breed had a higher daily gain than the crossbred rabbits (p<0.05), 18.0 and 16.7 g/d, respectively. There were no significant differences in feed intake, growth or feed conversion ratio due to sex. The digestibility coefficients of DM, organic matter, crude protein, crude fiber, neutral detergent fiber and acid detergent fiber were significantly lower (p<0.001) in the rabbits fed Ruzi grass. Breed and sex had no effect on digestibility. In conclusion, feeding head lettuce residue, Mimosa pigra and water spinach resulted in higher growth rate and digestibility than feeding Ruzi grass and can be recommended as alternative feeds.

• International Journal of Railway
• /
• 제2권2호
• /
• pp.43-49
• /
• 2009

Wear and rolling contact fatigue (RCF) defects are most important causes of rail damage, and often interaction competitive at present railway track. Head check is one of rolling contact fatigue (RCF) defects, and generally occurs in mild circular curves and transition curves that are set at both ends of sharp circular curves. Wear tends to limit the crack growth of head checks by removing the material from the RCF surface. In order to clarify the conditions of the occurrence and growth of head checks, the authors measured the interacting forces between wheels and rails and the angle of attack of wheelset, and carried out contact analyses using the actual profile data of wheels and rails. The effects of the lateral force, the contact geometry, and the wear rate at rail gauge comer on the formation of head checks were also analyzed by using the worn profiles of actual wheels and rails and the data obtained by a track inspection car. Some specific range of wear rate at the gauge comer was identified as having close relation with occurrence of head checks.

• Journal of Microbiology and Biotechnology
• /
• 제13권1호
• /
• pp.146-148
• /
• 2003

Effects of propylamine on conidial head formation and growth of Aspergillus niger and Aspergillus oryzae were analyzed. Propylamine inhibited conidial head formation in these two fungi, and the inhibitory effect of propylamine was not suppressed by the addition of potassium chloride at high concentration, which promotes conidial head formation in A. nidulans and A. oryzae. Propylamine also inhibited the growth of A. niger and A. oryzae by $41\%\;and\;32\%$, respectively, when the concentration of propylamine was $2\%$.

• 한국수산과학회지
• /
• 제46권6호
• /
• pp.970-972
• /
• 2013

We examined the relative growth of Microstomus achne during early life stages of laboratory-reared larvae and juveniles. Turning points in the relative growth of preanal length and upper jaw length against total length occurred during the settlement period (11.12-19.91 mm in total length). However, turning points in the relative growth of head length and eye diameter, as compared to total length, occurred during metamorphosis (17.57-22.47 mm in total length). Our results suggest that Microstomus achne concentrates its energy on the feeding apparatus (jaw) and digestive organs (intestine) rather than sensory or neural organs (eye, head) during early larval stage growth.

• 대한두경부종양학회지
• /
• 제20권2호
• /
• pp.128-134
• /
• 2004

Background and Objectives: Angiogenesis is the process of new blood vessel development from preexisting vessel. Angiogenenesis has been considered to be essential for the growth and expansion of a solid tumor. Vascular endothelial growth factor (VEGF), known as one of the most important vascular permeability factors, induces proliferation of endothelial cells, stiumulates angiogenesis, and increases vascular permeability. Several recents reports have documented that VEGF overexpression is associated with poor clinical outcomes in many maligmancies. The aims of this study were to determine whether microvessel density and VEGF expression are related to clinicopathologic factors such as age, sex, tumor size, tumor stage, and prognostic factors and to evaluate the relationship between VEGF expression and angiogenesis in benign and malignant thyroid tumors. Materials and Methods: The subjects were 65 patients (27 with papillary carcinoma, 27 with adenomatous hyperplasia, 11 with follicular adenoma) who underwent thyroidectomy from 1995 to 2001. Imuunohistochemistry was used to detect VEGF expression and microvessel density (MVD) in paraffin-embedded thryoid tumor specimens. Results: The intensity of the VEGF expression did not show stastically difference between benign and malignant thyroid tumors. There was no apparent correlation between VEGF expression and age, tumor size, T stage or scores of the AGES, AMES and MACIS systems. The neo-microvessel density was higher in the maligant tumor than the benign tumors. Also, higher neo-microvessel density was associated with metastases of the lymph nodes and scores of the AMES and AGES systems. Conclusion: Our results suggest that neo-microvessel vessel density may be a significant prognostic factor in the thyroid papillary carcinoma. But the VEGF expression does not appear to be an significant independent prognostic factor for thyroid papillary carcinoma.

• 대한후두음성언어의학회지
• /
• 제30권2호
• /
• pp.124-127
• /
• 2019

Vocal fold scarring is an intractable phonosurgical condition. The number of patients with vocal fold scars is increasing with the aging of society and with the increasing application of laryngeal microsurgery. Many methods are available to treat these, including voice therapy, stem cells, regenerative scaffolds, and growth factors. However, no standard treatment strategy has yet been established, and novel techniques are required. Basic fibroblast growth factor has been shown to be effective for the treatment of mild chronic vocal fold scarring. The combined use of basic fibroblast growth factor and regenerative scaffolds is currently under investigation. Here, we report a female patient in whom vocal fold scarring developed after two laryngeal microsurgeries. We performed laryngeal microsurgery to remove the scar tissue and used basic fibroblast growth factor and a collagen scaffold to promote healing. The patient's voice quality was greatly increased, and she was content with her voice after 2 years of follow-up. This is the first report of this methodology in Korea and is presented along with a review of the literature.

• Journal of Nutrition and Health
• /
• 제39권3호
• /
• pp.264-273
• /
• 2006

Elevated maternal plasma homocysteine concentrations have been associated with adverse pregnancy outcomes. Serum homocysteine levels may be affected by the MTHFR genotypes and the nutritional status of B vitamins including vitamin $B_2,\;B_6$, folate and vitamin $B_{12}$. We investigated whether postnatal growth measurements were influenced by maternal MTHFR genotypes and their mid-pregnancy serum vitamin B and homocysteine levels. In 130 pregnant women of 24-28 wks of gestation, the MTHFR genotypes, serum B vitamins and homocysteine concentrations were analyzed. Physical growth status was assessed in their offsprings by measuring height, weight, and head and chest circumferences from birth up to 24 months. Serum homocysteine levels were higher in the subjects with T/T genotype than those with the C/T or C/C. Heights and head and chest circumferences of offsprings from the T/T mothers were significantly lower than those from the C/C or C/T mothers only when the serum homocysteine levels were above the median. The mean height of offsprings from the T/T mothers was significantly lower than those from the C/C and C/T mothers. The mean weight and head circumferences of offsprings born from the mothers whose mid-term pregnancy PLP levels were in the lowest quartile was significantly lower than those from mothers in the highest quartile. Heights and head circumferences of offsprings from the T/T mothers were significantly lower than those from the C/C or C/T mothers only when the serum FAD levels were in the lowest quartile. These results suggest that postnatal growth up to 24 months may be influenced by the maternal C677T MTHFR genotypes, and mid-pregnancy serum homocysteine and vitamin B status.