• 한국미생물·생명공학회지
• /
• 제32권3호
• /
• pp.212-217
• /
• 2004

Glycosyl hydrolase family 26에 속하는 Bacillus subtilis WL-7 mannanase를 코드하는 유전자를 대장균에서 과잉 발현하였다. 아미노 말단의 signal peptide를 포함하거나 포함하지 않은 mannanase 유전자를 각각 pET24a(＋)에 도입하여 재조합 플라스미드 pETMAN과 pENS7를 제조하였다. 이들 플라스미드를 함유하는 Escherichia coli BL21(DE3)에서 mannanase를 발현시킨 결과 signal peptide가 제거된 mannanase유전자의 발현량이 매우 높았다. 그러나 배양온도 $37^{\circ}C$에서 pENS7를 함유한 재조합 대장균에서 과잉 발현된 mannanase는 대부분이 불활성 형태로 존재하였으며, 배양온도를 $31^{\circ}C$이하로 하였을 때 수용화 형태의 효소량이 증가하면서 효소활성이 높아졌다. IPTG에 의해 발현된 재조합 대장균의 균체파쇄 상등액 중에 존재하는 mannanase 활성은 배양온도 $25^{\circ}C$～28$^{\circ}C$에서 가장 높았으며, 전체 단백질량을 기준으로 볼 때는 배양온도 $31^{\circ}C$에서 비활성이 가장 높은 것으로 확인되었다.

• Biomolecules & Therapeutics
• /
• 제26권3호
• /
• pp.313-321
• /
• 2018

Anti-cancer drug resistance is a major problem in colorectal cancer (CRC) research. Although several studies have revealed the mechanism of cancer drug resistance, molecular targets for chemotherapeutic combinations remain elusive. To address this issue, we focused on the expression of cellular prion protein ($PrP^C$) in 5-FU-resistant CRC cells. In 5-FU-resistant CRC cells, $PrP^C$ expression is significantly increased, compared with that in normal CRC cells. In the presence of 5-FU, $PrP^C$ increased CRC cell survival and proliferation by maintaining the activation of the PI3K-Akt signaling pathway and the expression of cell cycle-associated proteins, including cyclin E, CDK2, cyclin D1, and CDK4. In addition, $PrP^C$ inhibited the activation of the stress-associated proteins p38, JNK, and p53. Moreover, after treatment of 5-FU-resistant CRC cells with 5-FU, silencing of $PrP^C$ triggered apoptosis via the activation of caspase-3. These results indicate that $PrP^C$ plays a key role in CRC drug resistance. The novel strategy of combining chemotherapy with $PrP^C$ targeting may yield efficacious treatments of colorectal cancer.

• 대한지역사회영양학회지
• /
• 제2권4호
• /
• pp.547-555
• /
• 1997

This study was conducted to assess the nutritional status of the elderly from low income areas and its relationship with the indices of immunity. Ninety nine(male : 28, female : 71) healthy, subjects aged over 65 years staying in homes in Seoul were assessed with regard to their dietary intake and biochemical measurements. Their mean daily energy intakes were 1256kcal and 109kcal for males and females respectively. Mean serum IgG were 2356mg/dl in men and 2161mg/dl for women, higher than the normal range. Mean serum $C_3$ were 120.9mg/dl and 130.6mg/dl for males and females respectively and mean $C_4$ were 30.6mg/dl and 31.9mg/dl. The mean $C_3$ and $C_4$ were within the normal range and the proportion of subjects whose $C_3$ and $C_4$ were at a higher level than the upper limit were 15.4$\%$ and 16.3$\%$ respectively. Complement $C_3$ showed significant correlation with serum albumin(p〈0.01), serum cholesterol(p〈0.00l, serum TG(p〈0.05), LDL-C(p$\ll$$\ll$$\ll$$\ll$$\ll$$\ll$$\ll$$\ll$$\ll$$\ll$$\ll$$\ll$$\ll$q0.001), VLDL-C(p$\ll$0.05), serum copper(p$\ll$0.05) and serum Ca(p$\ll$0.01). (Korean J Community Nutrition 2(4) : 547-555, 1997)

• 한국결정학회지
• /
• 제13권3_4호
• /
• pp.158-164
• /
• 2002

Tetrahomodioxa p-phenylcalix(4)arene dihexylether (C/sub 66/H/sub 68/O/sub 6/)를 합성하여 분자 및 결정 구조를 X-선 회절법으로 연구하였다. p-Phenylphenol의 탈수, 고리화 반응으로 만든 tetrahomodioxa p-phenylcalix(4)arene을 DMF에서 NaH와 hexyl iodide를 환류시켜 합성하였다. 결정은 사방정계이고 공간군은 P2₁2₁2₁, a =9.764(2), b = 16.167(2), c = 32.994(3) Å, V=5208(1) ų, Z= 4, Dc=1.221 gcm/sup -3/이다. 직접법으로 구조를 해석하였으며, 최소자승법으로 정밀화하여 최종 신뢰도 R 값은 2009개의 회절 반점에 대해 0.070 이었다. 이 분자는 마주 보고 있는 phenyl group 두 쌍이 거의 평행을 이루며, C-1,2-alternate conformation이고, lower rim의 1,3 위치에 hexyl 기가 치환된 비대칭 homooxacalixarene이다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제21권10호
• /
• pp.1441-1448
• /
• 2008

This experiment was carried out to study the carcass characteristics, chemical composition and fatty acid profile of the Longissimus muscle (LM) of bulls (10) and steers (17) finished in a pasture system. Animals (1/2 Zebu vs. 1/2 Aberdeen Angus) were fed in a pasture system (Hermatria altissima) and with a supplement of soybean meal, cracked corn, urea, limestone and mineral salts, twice a day. Both animal groups were slaughtered at 27 months of age, with an average 508.88 kg of live weight. Final weight, hot carcass weight and texture were similar (p>0.05) between bulls and steers. Carcass dressing, fat thickness, color and marbling were higher (p<0.02) in steers. Conversely, the Longissimus area was greater (p<0.05) in bulls. Moisture levels were higher (p<0.01) in bulls. Ash, crude protein, total lipids and total cholesterol levels were higher (p<0.10) in steers. C14:0, C16:0, C16:1 n-7 and C18:1 n-9 fatty acids percentages were higher (p<0.06) in steers. C16-1 n-10, i 17:0, C19:0, C18:2 n-6, C18:3 n-3, C20:2 n-3 C20:4 n-6, C20:5 n-3, C22:1 n-7, C22:4 n-6 and C22:5 n-3 fatty acids percentages were higher (p<0.05) in bulls. The percentage of the other fatty acids was similar (p>0.05) in bulls and steers. The levels of monounsaturated fatty acids were higher (p<0.02) in steers while polyunsaturated fatty acids, n-3, n-6, PUFA/SFA and n6:n3 ratios, were higher (p<0.05) in bulls. The CLA contents (mg/g lipids) were similar (p>0.10) in bulls and steers.

• 한국세라믹학회지
• /
• 제34권8호
• /
• pp.811-816
• /
• 1997

SiO2-P2O5-B2O3 glass soot was fabricated by flame hydrolysis deposition and their properties by SEM, XRD, TGA-DSC were investigated., The mechanism of consolidation process of a glass soot as a function of consolidation temperature was analyzed by SEM observations. In the XRD patterns, the crystalline peaks which seem to be generated from B2O3 and BPO4 were observed. When the temperature of heat treatment exceeded 105$0^{\circ}C$, the non-crystalline state of SiO2-P2O5-B2O3 glass was observed. In the TGA-DSC curves, the evaporation of water molecule by a sudden endothermic reaction was observed at 128$^{\circ}C$ and a broad endothermic peak was seen in the temperature range of 40$0^{\circ}C$-95$0^{\circ}C$, without any weight loss. Finally, this peak was began to recover its baseline at 953$^{\circ}C$. This point is equal to the temperature at which the densification begins. Furthermore, we observed that the addition of dopants such as P2O5 and B2O3 decrease the onset of consolidation temperature till 95$0^{\circ}C$.

• 한국식품영양학회지
• /
• 제8권3호
• /
• pp.192-198
• /
• 1995

Cheese milk를 기질로 하여 pronase 등 protease와 palanatase ML 등 lipase를 이용하여 EMC를 제조하였다. Cheese milk 가수분해에 관여하는 각 protease의 반응 조건을 살펴본 결과, pronase-3$0^{\circ}C$, pH 7.0, PANCREATIO-4$0^{\circ}C$, pH 8.0, pacific protease-3$0^{\circ}C$, pH 7.0과 Asp. Sp. 기원 protease-5$0^{\circ}C$, pH 8.0에서 최대의 활성을 보였으며, lipase의 반응 조건은 pancreatic lipase-5$0^{\circ}C$, pH 8.0, palatase ML-5$0^{\circ}C$, pH 7.0과 Candida cylindracea 기원 lipase-4$0^{\circ}C$, pH 6.0 이었다. 최적 반응 조건에서 가수분해를 행한 결과 반응 시간이 증가할수록 유리아미노산의 양과 유리지방산의 양이 증가하는 경향을 보였다. Pacific protease와 pronase에 의해 가수분해시 0.67mg/ml과 0.74 mg/ml의 유리 아미노산을 생성하였으며, 유리 아미노산 중 glutamic acid와 leucine이 가장 많은 함량을 보였다. Candida cylidracea 기원 lipase를 이용하여 가수분해시 가장 많은 유리 지방산 생성량을 보였다. 각 EMC의 지방산 조성을 살펴본 결과 butyric acid, palmitic acid, stearic acid와 oleic acid의 함량이 보였다. Pancreatin에 의해 가수분해 후 각 lipase를 사용하여 제조한 EMC의 관능검사 결과, pancreatic lipase를 이용한 EMC가 가장 쓴맛이 강하였고, palatase에 의한 EMC는 가장 바람직한 cheese 향기를 가지고 있다.

• 한국식품과학회지
• /
• 제6권1호
• /
• pp.6-11
• /
• 1974

Four new compounds; 2,2'-methylene-bis [3, 4, 6-trichloro ${{\beta}-(o-nitroanilino)$ propionoxy} benzene]; m.p. $200{\sim}202^{\circ}C,\;C_{31}H_{22}O_8N_4Cl_6$ 2,2'-methylene-bis [3, 4, 6-trichloro ${{\beta}-(p-nitroanilino)$ propionoxy} benzene]; m.p. $168-170^{\circ}C,\;C_{31}H_{22}O_8N_4Cl_6$ : 2,2'-Methylene-bis [3, 4, 6-trichloro ${{\beta}-(o-chloro-p-nitroanilino)$ propionoxy} benzene]; m.p. $170.5-172.5^{\circ}C,\;C_{31}H_{20}O_8N_4Cl_8$ : 2,2'-Methylene-bis [3, 4, 6-trichloro ${{\beta}-(c-methyl-p-nitroanilino)$ propionoxy} benzene]; m.p. $163-164^{\circ}C,\;C_{33}H_{26}O_8N_4Cl_6$-were synthesized by Mannich reaction from 2,2'-Methylene-bis (3, 4, 6-trichloroacetoxy benzene) and their antimicrobial activities against the microorganisms Staphylococcus aureus, Escherichia coli, Bacillus subtilis Natto, Brevibacterium ammoniagenes, Candida tropicalis, Rhodotorula glutinis, Pseudomonas ovalis, Aspergillus candidus Link, Aspergillus awamori Nakazawa. Aspergillus niger var. Tieghem, Aspergillus usami Sakakuchi, Penicillium notatum-were tested. 2,2'-methylene-bis [3, 4, 6-trichloro ${{\beta}-(o-nitroanilino)$ propionoxy} benzene] showed a strong antimicrobial activity against Bacilus subtilis Natto and Brevibacterium ammoniagenes.

• Journal of Ginseng Research
• /
• 제19권2호
• /
• pp.181-187
• /
• 1995

Cylindvocarpon destmtalns isolate CY-92-01, pathogen of root-rot of Panax ginseng showed t the maximum mycelial growth on the Czapek solution agar among the thirteen kinds of media. Five isolates (Isolate CY-92-01, CY-92-03, CY-92-07, CY-94-01, CY-94-02) of C. destructan from various growth stages of p. ginseng recovered from several geographical sites also showed maximum growth in the Czapek-Dox broth compared with potato dextrose broth and V-8 juice broth. Rapid growth rate was maintained until 12 days after inoculation on the Czapek-Dox broth and mycelial weight was somewhat constant until 20 days. After 30 days of incubation, the mycelial weight began to decrease. The fungal growth occurred from 5$^{\circ}C$ to $25^{\circ}C$ and optimum temperature for growth was 2$0^{\circ}C$. Mycelial weight orderly decreased at 15, 25, 10, and 5$^{\circ}C$. Quantitative measurement was impossible at 5$^{\circ}C$. No fungal growth was occurred at the temperature higher than 3$0^{\circ}C$. Growth was observed at all tested pH ranges from 2.8 to 8.0. Optimum pH for growth was 4.0~5.0 followed by pH 3.3~3.5 and 5.4~6.0. The least growth occurred at pH 2.8.

• 대한전자공학회논문지SD
• /
• 제38권6호
• /
• pp.398-403
• /
• 2001

본 논문에서는 6H-SiC의 유효 이온화 계수를 추출하였고, 이 이온화 계수를 이용하여 6H-SiC p＋n 접합의 해석적 항복 전압 식을 유도하였다. 해석적 항복 전압 결과는 10/sup 15/ cm/sup -3/ ∼ 10/sup 18/ cm/sup -3/의 농도 범위에서 Dmitriev의 수치적 결과［3］ 및 Cree Research의 실험 결과［9］와 비교하여 잘 일치하였다.