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Recently, it has been suggested that isoflurane might reduce dopamine release from rat midbrain dopaminergic neurons, the neurobiological substrate implicated in the reinforcing effects of abused drugs and nondrug rewards. However, little is known about effects of isoflurane on neurobehavioral activity associated with chronic exposure to psychoactive substances.The present study was designed to investigate the effects of isoflurane on cocaine-reinforced behavior. Using behavioral paradigm in rats, we evaluated the effects of isoflurane on cocaine self-administration under fixed ratio (FR) and progressive ratio (PR) schedules of reinforcement. We also tested the effects of isoflurane on lever responding by nondrug reinforcers (sucrose and food) in drug-naive rats to control for the nonselective effects of isoflurane on cocaine- and nicotine-taking behavior. To further assess the ability of isoflurane to modulate the motivation for taking a drug, we evaluated the effects of isoflurane on nicotine self-administration. Using different groups of rats, the effects of isoflurane on the locomotor activity induced by a single intraperitoneal injection of cocaine (15 mg/kg) were also examined.Isoflurane significantly suppressed the self-administration of cocaine and nicotine without affecting food consumption. Unlike food-reinforced responding, responding for sucrose reinforcement was decreased by isoflurane. Isoflurane reduced breaking points under a PR schedule of reinforcement in a dose-dependent manner, indicating its efficacy in decreasing the incentive value of cocaine. Isoflurane also attenuated acute cocaine-induced hyperlocomotion.The results provided evidence that isoflurane decreases cocaine- and nicotine-reinforced responses, while isoflurane effect is not selective for cocaine- and nicotine-maintained responding. These results suggest that isoflurane inhibitions of cocaine- and nicotine-maintenance responses may be related to decreased effects of dopamine, and further investigation will need to elucidate this relationship.

Fibrinolytic enzyme genes (aprE2, aprE176, and aprE179) were introduced into the Bacillus subtilis 168 chromosome without any antibiotic resistance gene. An integration vector, pDG1662, was used to deliver the genes into the amyE site of B. subtilis 168. Integrants, SJ3-5nc, SJ176nc, and SJ179nc, were obtained after two successive homologous recombinations. The integration of each fibrinolytic gene into the middle of the amyE site was confirmed by phenotypes (Amy(-), Spec(S)) and colony PCR results for these strains. The fibrinolytic activities of the integrants were higher than that of B. subtilis 168 by at least 3.2-fold when grown in LB broth. Cheonggukjang was prepared by inoculating each of B. subtilis 168, SJ3-5nc, SJ176nc, and SJ179nc, and the fibrinolytic activity of cheonggukjang was 4.6 ± 0.7, 10.8 ± 0.9, 7.0 ± 0.6, and 8.0 ± 0.2 (U/g of cheonggukjang), respectively at 72 h. These results showed that construction of B. subtilis strains with enhanced fibrinolytic activities is possible by integration of a strong fibrinolytic gene via a marker-free manner.

A gamma-aminobutyric acid (GABA)-producing microorganism was isolated from jeot-gal (anchovy), a Korean fermented seafood. The isolate, A156, produced GABA profusely when incubated in MRS broth with monosodium glutamate (3% (w/v)) at 37°C for 48 h. A156 was identified as Lactobacillus sakei by 16S rRNA gene sequencing. The GABA conversion yield was 86% as determined by GABase enzyme assay. The gadB gene encoding glutamate decarboxylase (GAD) was cloned by PCR. gadC encoding a glutamate/GABA antiporter was located immediately upstream of gadB. The operon structure of gadCB was confirmed by RT-PCR. gadB was overexpressed in Escherichia coli BL21(DE3) and recombinant GAD was purified. The purified GAD was 54.4 kDa in size by SDS-PAGE. Maximum GAD activity was observed at pH 5.0 and 55°C and the activity was dependent on pyridoxal 5'-phosphate. The Km and Vmax of GAD were 0.045 mM and 0.011 mM/min, respectively, when glutamate was used as the substrate.

A cryptic plasmid, pJY33, from Weissella cibaria 33 was characterized. pJY33 was 2365 bp in size with a GC content of 41.27% and contained two putative open reading frames (ORFs). orf1 encoded a putative hypothetical protein of 134 amino acids. orf2 was 849 bp in size, and its putative translation product exhibited 87% identity with a replication initiation factor from a plasmid from W. cibaria KLC140. A Weissella - Escherichia coli shuttle vector, pJY33E (6.5 kb, Em r ), was constructed by ligation of pJY33 with pBluescript II SK(−) and an erythromycin resistance gene (Em r ). pJY33E replicated in Lactococcus lactis , Leuconostoc citreum , Lactobacillus brevis, Lactobacillus plantarum, and Weissella confusa . A single-stranded DNA intermediate was detected from Lb. brevis 2.14 harbouring pJY33E, providing evidence for rolling-circle replication of pJY33. Most Lb. brevis 2.14 cells (85.9%) retained pJY33E after one week of daily culturing in MRS broth without Em. An aga gene encoding α-galactosidase (α-Gal) from Leuconostoc mesenteroides was successfully expressed in Lb. brevis 2.14 using pJY33E, and the highest level of α-Gal activity (36.13 U/mg protein) was observed when cells were grown on melibiose.

Reactive oxygen species (ROS) are widely generated in biological processes such as normal metabolism and response to xenobiotic exposure. While ROS can be beneficial or harmful to cells and tissues, generation of ROS by diverse anti-cancer drugs or phytochemicals plays an important role in the induction of apoptosis. We recently identified a derivative of naphthalene, MS-5, that induces apoptosis of an ovarian cell, CAOV-3. Interestingly, MS-5 induced apoptosis by down-regulating the ROS. Cell viability was evaluated by water-soluble tetrazolium salt (WST-1) assay. Apoptosis was evaluated by flow cytometry analysis. Intracellular ROS (H₂O₂), mitochondrial superoxide, mitochondrial membrane potential (MMP) and effect on cycle were determined by flow cytometry. Protein expression was assessed by western blotting. The level of ATP was measured using ATP Colorimetric/Fluorometric Assay kit. MS-5 inhibited growth of ovarian cancer cell lines, CAOV-3, in a concentration- and time-dependent manner. MS-5 also induced G1 cell cycle arrest in CAOV-3 cells, while MS-5 decreased intracellular ROS generation. In addition, cells treated with MS-5 showed the decrease in MMP and ATP production. In this study, we found that treatment with MS-5 in CAOV-3 cells induced apoptosis but decreased ROS level. We suspect that MS-5 might interfere with the minimum requirements of ROS for survival. These perturbations appear to be concentration-dependent, suggesting that MS-5 may induce apoptosis by interfering with ROS generation. We propose that MS-5 may be a potent therapeutic agent for inducing apoptosis in ovarian cancer cell through regulation of ROS.

The aprE2 gene with its prosequence from Bacillus subtilis CH3-5 was overexpressed in Escherichia coli BL21(DE3) by using plasmid pET26b(+). After IPTG induction, active and mature AprE2 was produced when cells were grown at 20°C, whereas inactive and insoluble enzyme was produced in a large amount when cells were grown at 37°C. The insoluble fraction was resuspended with 6 M guanidine-HCl and dialyzed against 2 M Tris-HCl (pH 7.0) or 0.5 M sodium acetate (pH 7.0) buffer. Then active AprE2 was regenerated and purified by a Ni-NTA column. Purified AprE2 from the soluble fraction had a specific activity of 1,069.4 ± 42.4 U/mg protein, higher than that from the renatured insoluble fraction. However, more active AprE2 was obtained by renaturation of the insoluble fraction. AprE2 was most stable at pH 7 and 40°C, respectively. The fibrinolytic activity of AprE2 was inhibited by PMSF, but not by EDTA and metal ions. AprE2 degraded Aα and Bβ chains of fibrinogen quickly, but not the γ-chain. AprE2 exhibited the highest specificity for N-succinyl-Ala-Ala-Pro-Phe-pNA. The Km and kcat/Km of AprE2 was 0.56 mM and 3.10 × 10(4) S(-1) M(-1), respectively.

We report an experimental optimization of the cleaning process in the fabrication of flexible polymer solar cells using an indium tin oxide (ITO) coated poly(ethylene naphthalate) (PEN) substrate. The effects of the solubility parameters of the cleaning solvents on the occurrence of ITO cracks have been systematically investigated. The experimental results showed that the ITO cracks caused during the ultrasonic cleaning process were mainly affected by differences between the solubility parameters of the solvent and that of the PEN substrate, not by direct interaction between the solvent and the ITO layer. Our results provide a simple method for reducing ITO cracks during wet cleaning processes by selecting solvents with solubility parameters which differ significantly from those of the flexible substrates.

The syndiotactic and atactic poly (2-N-carbazoylrnethyl) styrenes were obtained by a half-titanocene catalyst and a radical initiator for the investigation of photophysical properties, especially excimer formation. The atactic polymer exhibited only monomer emission, but the syndiotactic polymer showed both excimer emission and monomer emission resulting from the partial overlapping arrangement of carbazole pendants, The emission band of syndiotactic polymer was considerably dependent on solution concentration and temperature, however atactic polymer was independent because the excimer formation of syndiotactic helical conformation was more favorable than that of the random coil conformation of atactic polymer.

A 4661 bp cryptic plasmid, pFMBL1, was isolated from Leuconostoc mesenteroides SY2, an isolate from Kimchi, and characterized. Nucleotide sequence analysis revealed two open reading frames, orf1 and orf2. orf2 was 453 bp in size and its translation product had 58% identity with a putative protein possibly involved in the replication of pTXL1, a cryptic plasmid from L. mesenteroides ssp. mesenteroides Y110. RNA transcript from orf2 was detected but not from orf1 or intergenic region. Minimum 3.5 kb fragment encompassing orf1 and orf2 was required for the replication of pFMBL1 and employed for the construction of Escherichia coli-Leuconostoc shuttle vector, pSJ33E. L. mesenteroides SY1 (another Kimchi isolate), Leuconostoc ssp., and Lactobacillus brevis were successfully transformed with pSJ33E, and the transformation efficiencies were ranged between 1.1 × 101 and 4 × 105 transformants/μg DNA. No single-stranded DNA intermediate was detected from L. mesenteroides SY1 cells harboring pSJ33E, indicating that pFMBL1 probably replicated via θ-type mechanism. pSJ33E was stably maintained in L. mesenteroides SY1 in the absence of erythromycin (Em, 5 μg/ml) and after 1 month of daily subculturing in MRS broth without selective pressure, three percent of cells still retained pSJ33E.

Four lactic acid bacteria (LAB), Lactobacillus paraplantarum KM, Enterococcus durans KH, Streptococcus salivarius HM and Weissella confusa JY, were isolated from humans and tested for their capabilities of converting isoflavone glucosides to aglycones in soymilk. Changes in growth, pH, and titratable acidity (TA) were investigated during fermentation at 37 degrees C for 12 h. After 6 to 9 h of fermentation, each population of 4 LAB reached 10(8) to 10(9) CFU/mL. The initial pH of 6.3 +/- 0.1 decreased while the TA of 0.13%+/- 0.01% increased as fermentation proceeded, resulting in the final range between 4.1 +/- 0.2 and 4.6 +/- 0.1 for pH and between 0.51%+/- 0.02% and 0.67%+/- 0.06% for TA after the 12 h of fermentation. The glucoside concentrations were significantly decreased in soymilks fermented with either L. paraplantarum KM, S. salivarius HM, or W. confusa JY with fermentation time (P < 0.05). L. paraplantarum KM was the best in percent conversion of glucosides to corresponding aglycones, resulting in 100%, 90%, and 61% hydrolysis of genistin, daidzin, and glycitin, respectively, in 6 h. Consequently, the aglycone concentrations in soymilk fermented with L. paraplantarum KM were 6 and 7-fold higher than the initial levels of daidzein and genistein, respectively, after 6 h of fermentation. Changes in the daidzin and genistin levels were not significant in soymilk fermented with E. durans KH. The rates of hydrolysis of glucosides varied depending on the species of LAB. Especially, L. paraplantarum KM seems to be a promising starter for bioactive-fermented soymilk based on its growth, acid production, and isoflavone conversion within a short time.

A Bacillus species, EMD4, with strong antibacterial activity was isolated from ganjang (soy sauce) and identified as B. subtilis. B. subtilis EMD4 strongly inhibited the growth of B. cereus ATCC14579 and B. thuringiensis ATCC33679. The antibacterial activity was stable at pH 3-9 but inactive at pH 10 and above. The activity was fully retained after 15 min at 80°C but reduced by 50% after 15 min at 90°C. The activity was completely destroyed by proteinase K and protease treatment, indicating its proteinaceous nature. The bacteriocin (BacEMD4) was partially purified from culture supernatant by ammonium sulfate precipitation, and QSepharose and Sephadex G-50 column chromatographies. The specific activity was increased from 769.2 AU/mg protein to 8,347.8 AU/mg protein and the final yield was 12.6%. The size of BacEMD4 was determined to be 3.5 kDa by Tricine SDS-PAGE. The N-terminal amino acid sequence was similar with that of Subtilosin A. Nucleotide sequencing of the cloned gene confirmed that BacEMD4 was Subtilosin A. BacEMD4 showed bactericidal activity against B. cereus ATCC14579.

Lactic acid bacteria (LAB) were isolated from Kimchi, a Korean traditional fermented vegetable food. LAB accumulating GABA (γ-aminobutyric acid) in the culture media were screened by TLC analysis. One isolate, GU240, produced the highest amount of GABA among the 3,000 isolates and identified as a Lactobacillus zymae strain. Glutamate decarboxylase (GAD) gene was cloned and over-expressed in E. coli BL21(DE3) using pET26b(+). The recombinant GAD was purified by using a Ni–NTA column. Its size was 53 kDa by SDS-PAGE. Maximum GAD activity was at pH 4.5 and 41 °C and the activity was dependent on pyridoxal 5′-phosphate. Km and Vmax of LzGAD were 1.7 mM and 0.01 mM/min, respectively, when glutamate was used as a substrate.

Bacillus subtilis CH3-5 was isolated from cheonggukjang prepared according to traditional methods. CH3-5 secreted at least four different fibrinolytic proteases (63, 47, 29, and 20 kDa) into the culture medium. A fibrinolytic enzyme gene, aprE2, encoding a 29 kDa enzyme was cloned from the genomic DNA of CH3-5, and the DNA sequence determined. aprE2 was overexpressed in heterologous B. subtilis strains deficient in extracellular proteases using a E. coli-Bacillus shuttle vector. A 29 kDa AprE2 band was observed and AprE2 seemed to exhibit higher activities towards fibrin rather than casein.

A Lactobacillus paraplantarum strain producing a bacteriocin was isolated from kimchi using the spot-on-the lawn method and named L. paraplantarum C7. The bacteriocin, paraplantaricin C7, was found to inhibit certain Lactobacillus strains, including L. plantarum, L. pentosus, and L. delbrueckii subsp. lactis. It also inhibited Enterococcus faecalis, yet did not inhibit most of the other LAB (lactic acid bacteria) tested. The maximum level of paraplantaricin C7 activity was observed under the culture conditions of 25 degrees C and a constant pH of 4.5. Paraplantaricin C7 retained 90% of its activity after 10 min of treatment at 100 degrees C and remained stable within a pH range of 2-8. Based on a culture supernatant, paraplantaricin C7 was purified by DEAE-Sephacel column chromatography and C18 reverse-phase HPLC. SDS-PAGE and activity staining were then conducted using the purified paraplantaricin C7, and its molecular mass determined to be about 3,800 Da. The 28 N-terminal amino acids from the purified paraplantaricin C7 were determined, and the structural gene encoding paraplantaricin C7, ppnC7, was cloned by PCR using degenerate primers based on the N-terminal amino acid sequence. The nucleotide sequences for ppnC7 and other neighboring orfs exhibited a limited homology to the previously reported plantaricin operon genes. Paraplantaricin C7 is a novel type II bacteriocin containing a double glycine leader sequence.

분자내 전하이동(intramolecular charge transfer, ICT)이 가능한 도너- $\pi$ -억셉터(D- $\pi$ -A)타입의 발색단 을 근간으로 한 폴리머를 신규 합성하였다. 이 폴리머는 UV-visible spectra 측정결과 용액 상태에서 뿐만 아니라 고체박막 상태에서도 카르보닐기(carbonyl group)에서 기인하는 흡수와 함께 ICT에 의한 장파장 영역에서의 흡수가 관 찰되었다. $Eu^{3+}$ 이온의 첨가에 의해 장파장영역에서 일어나는 흡수의 적색이동(red shift)을 유도하였으며, 더불어 용 액과 박막의 색상도 황색에서 적색으로 변화하는 것이 관찰되었다. 합성된 고분자의 형태 및 유기 용매에 대한 용해도 는 가교제의 함량에 따라 다양한 특성을 나타내었다. 또한, 첨가된 가교제의 함량과 $Eu^{3+}$ 이온의 첨가는 성막 특성의 향상을 유도하였다. 【Donor- $\pi$ -acceptor (D- $\pi$ -A) type chromophore-based polymers were newly synthesized. These polymers exhibited absorption peak due to intramolecular charge transfer (ICT) in a visible range as well as absorption peak due to carbonyl group in both solution and film state by measuring UV visible spectra. The addition of $Eu^{3+}$ ion into the polymers induced red-shift in absorption due to ICT and the color changes from yellow to red in the solution and film were observed by naked eyes. The contents of crosslinking agent influenced the features and solubility of the polymers. In addition, the contents of crosslinking agent and the $Eu^{3+}$ ion addition improved film-forming ability.】