• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.389-398
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• 2009

Development of expression vectors is important for the basic and applied researches on kimchi LAB (lactic acid bacteria). An expression vector, pSJE6c was constructed by inserting P6C promoter sequence from Lactococcus lactis into pSJE, a shuttle vector for E. coli and Leuconostoc species. To test the efficiency of pSJE6c, aga ($\alpha$-galactosidase) and lacZ ($\beta$-galactosidase) genes were expressed in Lactobacillus brevis 2.14. Compared to the pSJE, expression levels of both genes were increased, indicating P6C promoter was better than indigenous promoters. Enzyme activities of L. brevis cells harboring pSJE6caga (pSJE6c with aga) or pSJE6Z (pSJE6c with lacZ) were 1.5-2 fold higher than those with pSJEaga (pSJE with aga) or pSJEZ (pSJE with lacZ). More RNA transcripts were detected in cells harboring pSJE6c based recombinant plasmid. The results indicated that heterologous gene expressions in kimchi LAB could be improved significantly by use of efficient expression vectors.

• Journal of Life Science
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• v.24 no.9
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• pp.995-1000
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• 2014

The studies of marine viruses in terms of viral isolation and detection have been limited due to the high mutation rate and genetic diversity of marine viruses. Of the modern methods currently used to detect marine viruses, serological methods based on enzyme-linked immunosorbent assay (ELISA) are the most common. They depend largely on the quality of the antibodies and on highly purified suitable antigens. Recently, a new experimental system for using viral capsid protein as an antigen has been developed using the yeast surface display (YSD) technique. In the present study, the capsid protein gene of the red-spotted grouper nervous necrosis virus (RGNNV) was expressed and purified via YSD and HA-tagging systems, respectively. Two regions of the RGNNV capsid protein gene, RGNNV1 and RGNNV2, were individually synthesized and subcloned into a yeast expression vector, pCTCON. The expressions of each RGNNV capsid protein in the Saccharomyces cerevisiae strain EBY100 were indirectly detected by flow cytometry with fluorescently labeled antibodies, while recognizing the C-terminal c-myc tags encoded by the display vector. The expressed RGNNV capsid proteins were isolated from the yeast surface through the cleavage of the disulfide bond between the Aga1 and Aga2 proteins after ${\beta}$-mercaptoethanol treatment, and they were directly detected by Western blot using anti-HA antibody. These results indicated that YSD and HA-tagging systems could be applicable to the expressions and purification of recombinant RGNNV capsid proteins.

• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.411-416
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• 2002

Bacillus macerans cyclodextrin glucanotransferase (CGTase) was expressed on the cell surface of Saccharomyces cerevisiae by fusing with Aga2p linked to the membrane-anchored protein, Aga1p. The surface display of CGTase was confirmed by immunofluorescence microscopy and its enzymatic ability to form ${\alpha}$-cyclodextrin from starch. The maximum surface-display of CGTase was obtained by growing recombinant S. cerevisiae at $20^{\circ}C$ and pH 6.0. S. cerevisiae cells displaying CGTase on their surface consumed glucose and maltose, inhibitory byproducts of the CGTase reaction, to enhance the purity of produced cyclodextrins. Accordingly, the experimental results described herein suggest a possibility of using the recombinant S.cerevisiae anchored with bacterial CGTase on the cell surface as a whole-cell biocatalyst for the production of cyclodextrin.

• Journal of Pharmaceutical Investigation
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• v.23 no.4
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• pp.217-223
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• 1993

The combined products of antacid and anti-ulcer agent were prepared with antacid composed of aluminium hydroxide dried gel, magnesium hydroxide and simethicone with a ratio of 1:1:0.1 (M) and anti-ulcer agent, aceglutamide aluminium (AGA). The efficacy of antacid was evaluated in vitro with Fuchs, Johnson-Duncan and Rosset-Rice methods and in vivo using an aspiration method in rat. The addition of anti-ulcer agent did not affect the neutralizing capacity of M significantly. The combined products with the M/AGA ratios of 2.3:1 and 3.4:1 produced the maximum pH of $4.0{\sim}5.8$ and the duration time of $64{\sim}137$ min in vitro test. The in vivo neutralizing test in rats showed the rapid increase of gastric pH up to 3.5 within 30 min and the gastric pH of $4{\sim}6$ was kept for 5 hr.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.360-367
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• 2006

The endoinulinase gene (inu1) from Pseudomonas mucidolens was expressed on the cell surface of Saccharomyces cerevisiae by fusing with Aga2p linked to the membrane anchored protein, Aga1p. The inu1 gene of P. mucidolens was subcloned into the surface display vector, pCTcon (GAL1 promoter). The constructed plasmid, pCTENIU (8.5kb), was then introduced to S. cerevisiae EBY100 cells and the yeast transformants selected on synthetic defined media lacking uracil and inulin-containing media. The inu1 gene under the control of the GAL1 promoter was successfully expressed in the yeast transformants, and the surface display of endoinulinase confirmed by immunofluorescence microscopy, along with its enzymatic ability to form inulooligosaccharides (IOSs) from inulin. The total endoinulinase activity reached about 2.31 units/ml when the yeast transform ants were cultivated on a YPDG medium. To efficiently hydrolyze the inulin, various reaction conditions were examined, including the pH, temperature, and inulin source. The optimized conditions were then determined as follows: pH, 7.0; temperature, $50^{\circ}C$; inulin source, Jerusalem artichoke. Under the optimized condition and 46 units of endoinulinase per g of inulin, IOSs started to be produced after 10 min of enzymatic reaction. The highest yield, 71.2% of IOSs, was achieved after 30 h of reaction without any significant loss of the initial enzyme activity. As a result of the reaction with inulin, IOSs consisting of inulobiose (F2), inulotriose (F3), inulotetraose (F4), and inulopentaose (F5) were produced, and F4 was the major product.

• Clinical and Experimental Pediatrics
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• v.46 no.5
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• pp.447-453
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• 2003

Purpose : This study was performed to compare complications and perinatal factors according to the birth weight groups in the infants of diabetic mothers(IDM). Methods : Three hundred and one singleton diabetic mothers and their babies of more than 30 weeks' gestational age admitted in the department of Pediatrics, Chonnam University Hospital from January 1996 to March 2002 were enrolled. Complications and perinatal factors were compared between large for gestational age(LGA) and appropriated for gestational age(AGA) infants. Results : Hypomagnesemia was observed in 37.5%, jaundice in 21.3%, hypoglycemia in 11.1%, hypocalcemia in 7.0%, and birth injury in 19.6%. Congenital anomaly was noted in 24.9% with cardiovascular anomaly most commonly. In the LGA group, the frequencies of jaundice, hypoglycemia, tachypnea, and birth injuries were higher, and the interventricular septum was thicker than the AGA group. In the LGA group, Cesarean section rate, maternal height, weight before pregnancy, weight gain during pregnancy, and the incidence of unawareness of gestational DM were significant compared with the AGA group. Conclusion : In the LGA group, the frequencies of jaundice, hypoglycemia, tachypnea, and birth injuries were higher, and the interventricular septum was thicker than the AGA group. In the LGA group, maternal height, weight before pregnancy and weight gain during pregnancy were larger, and the incidence of unawareness of gestational DM was higher compared with the AGA group. These results suggest that careful examination and management are needed to detect the high risk, pregnant DM mothers with possible LGA babies.

• Progress in Medical Physics
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• v.12 no.1
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• pp.59-70
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• 2001

Adrenal chromaffin cells secrete catecholamine in response to acetylcholine. The secretory response has absolute requirement for extracellular calcium, indicating that $Ca^{2+}$ influx through voltage operated $Ca^{2+}$ channels is the primary trigger of the secretion cascade. Although the existence of various types of $Ca^{2+}$ channels has been explored using patch clamp technique in adrenal chromaffin cells, there is still disagreement with the types of $Ca^{2+}$ channels existed in different species. Therefore, we have tried to identify several distinct types of $Ca^{2+}$ channels in rat chromaffin cells. By using nicardipine(L type channel blocker), $\omega$-CgTx GVIA(N type channel blocker), and $\omega$-AgaTx VIA(P type channel blocker), it was identified that L, N, and P type $Ca^{2+}$ channel exist in rat adrenal chromaffin cells and the order of contribution of each channel type to whole cell $Ca^{2+}$ current was L type> N type> P type. type> P type.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.43-45
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• 2013

Background: The aim of this epidemiological study was to establish the laterality of breast cancer (BC) and its association with size, receptor status of the primary tumor and bone metastasis (BM) in a local population. Materials and Methods: This retrospective study included cases of BC from Jan-2009 to Dec-2011 who were referred for metastatic work up or follow up survey with Technetium-99m MDP bone scan (BS) to the Nuclear Medicine Department of Karachi Institute of Radiotherapy and Nuclear Medicine (KIRAN). A total of 384 patients out of 521 were included and all reviewed for age, primary tumor size (PTS), laterality, receptor status like estrogen receptor (ER) progesterone receptor (PR) and Her-2-Neu receptor, presence or absence of BM with sites of involvement and time interval between diagnosis of BC and appearance of BM. Results: The left to right sided BC proportion was significantly higher than unity (59%:41%; p<0.001). The right sided BC was observed in younger age group (46:52 years; p<0.0001) and with a smaller PTS than the left sided (3.43:4.15 cm; p<0.0001). The patients with BM had relatively higher negative receptor status with a significant predominance of right sided BC. The overall incidence of BM on BS was 28% and relatively higher in right than left breast (33%:24% p=0.068). The average number of BM sites was also significantly greater for the right side (6:4, P<0.0001). The % cumulative risk of BM in right breast was noted at significantly smaller PTS than left side with log rank value of 5.579; p<0.05. The Kaplan Meier survival plot for event free survival of BM in left sided BC was significantly higher than for the right side (log rank value=4.155, p<0.05), with an earlier appearance of BM in right BC. Conclusions: 1) A left sided predominance of BC was seen in local population; 2) right sided BC had a more aggressive behavior with extensive and earlier appearance of BM at relatively younger age, smaller PTS and receptor (s) negativity.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.183-188
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• 2013

Background: Breast cancer (BC), the most common female cancer in Pakistan, is associated with a very high mortality. However, the roles of individual risk factors for BC among Pakistani women are still controversial. To assess potential risk factors for BC, a matched case-control study was conducted in two tertiary care hospitals of Karachi, Pakistan. Materials and Methods: The study population included 297 pathologically confirmed incident cases of BC patients diagnosed between January 2009 and December 2010. 586 controls without any history of BC were matched on hospital and ${\pm}5$ years of ages. Results: Positive family history of BC (MOR=1.72; 95%CI: 1.10, 2.80 for first degree vs. none), single marital status (MOR=1.55; 95%CI: 1.10, 2.39 for single/divorced/widowed women vs. married women), older age at menopause (MOR=3.92; 95%CI: 2.52, 6.18 for menopausal women aged below 45 years, MOR=6.42; 95%CI: 3.47, 11.98 for menopausal women above 45 years of age compared with premenopausal women) conferred an increased risk of BC for women. Increasing parity decreased the risk of BC (MOR=0.90; 95%CI: 0.85, 0.97 for each live birth). Intake of Vitamin D supplements (MOR=0.30; 95%CI: 0.12, 0.81 for ${\leq}3$ years and MOR=0.27; 95%CI: 0.13, 0.56 for >3 years) was protective compared to non-users of Vitamin D. Conclusions: This study confirmed only few of the recognized risk factors in Pakistani women. The protective effect of Vitamin D is important from public health perspective and needs to be further explored through a randomized controlled trial.

• Journal of Microbiology and Biotechnology
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• v.13 no.2
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• pp.287-291
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• 2003

Botulinum neurotoxin type A (BONT/A) is an extremely potent toxin, which is produced by Clostridium botulinum. The light chain of this protein (BONT/A LC), which is known as a zinc endopeptidase, cleaves SNAP-25 involved in the exocytosis process. In this work, the expression of recombinant BoNT/A LC in E. coli is described. The BONT/A LC gene of C. botulinum contains a high frequency of the arginine AGA and isoleucine ATA codons that are rarely used in genes of E. coli, hampering the translation of recombinant protein. The argD and ilex tRNA genes were cloned into pACYC184 vector, resulting in pAAD131X plasmid. The translational stress of the toxin gene related to codon bias was reversed by fupplernentation of the AGA arginyl tRNA of T4 phage and AUA isoleucyl tRNA of E. coli. This system may be applicable for the expression of a variety of AT-rich heterologous genes in E. coli.