• Food Science and Preservation
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• v.31 no.1
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• pp.149-160
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• 2024

Dextran is a glucose homo-polysaccharide with a predominantly α-1,6 glycosidic linkage of microbial source and is known to be produced primarily by lactic acid bacteria. However, it can also be obtained through the dextran dextrinase of acetic acid bacteria (Gluconobacter oxydans). The dextrin-based dextran was obtained from rice starch using G. oxydans fermentation of rice hydrolysate, and its properties were studied. Both dextrin- and rice hydrolysate-added media maintained the OD value of 6 after 20 h of incubation with acetic acid bacteria, and the gel permeation chromatography (GPC) analysis of the supernatant after 72 h of incubation confirmed that a polymeric material with DP of 480 and 405, which was different from the composition of the substrate in the medium, was produced. The glucose linkage pattern of the polysaccharide was confirmed using the proton nuclear magnetic resonance (¹H-NMR) and the increased α-1,4:α-1,6 bond ratio from 0.23 and 0.13 to 1:2.37 and 1:4.4, respectively, indicating that the main bonds were converted to α-1,6 bonds. The treatment of dextrin with a rat-derived alpha-glucosidase digestive enzyme resulted in a slow release of glucose, suggesting that rice hydrolysate can be converted to dextran using acetic acid bacteria with glycosyltransferase activity to produce high-value bio-materials with slowly digestible properties.

• Clinical and Experimental Reproductive Medicine
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• v.35 no.4
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• pp.309-317
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• 2008

Objectives: The aim of this study was to evaluate the usefulness of Anti-mullerian hormone (AMH) as a predictive marker for ovarian response and cycle outcome in IVF cycles. Methods: From Jan., to Aug., 2007, 111 patients undergoing IVF/ICSI stimulated by short or antagonist protocol were selected. On cycle day 3, basal serum AMH level and FSH level were measured. The correlation between basal serum AMH or FSH, and COH outcome was analyzed and IVF outcome was compared according to the AMH levels. To determine the threshold value of AMH for poor- and hyper-response, ROC curve was analyzed. Results: Serum AMH showed higher correlation coefficient (r=0.792, p<0.001) with the number of retrieved mature oocyte than serum FSH (r=-0.477, p<0.001). According to ovarian response, FSH and AMH leves showed significant differences among poor, normal, and hyperresponder. For predicting poor (${\leq}2$ oocytes) and hyperresponse (${\geq}17$ oocyets), AMH cut-off values were 0.5 ng/ml (the sensitivity 88.9% and the specificity 89.5%) and 2.5 ng/ml (sensitivity 85.7%, specificity 87.0%), respectively. According to the AMH level, patients were divided into 3 groups: low (${\leq}0.60\;ng/ml$), normal ($0.60{\sim}2.60\;ng/ml$), and high AMH (${\geq}2.60\;ng/ml$). The number of retrieved mature oocytes was significantly higher ($2.7{\pm}2.2$, $8.1{\pm}4.8$, $16.5{\pm}5.7$) and total gonadotropin dose was lower ($3530.5{\pm}1251.0$, $2957.1{\pm}1057.6$, and $2219.2{\pm}751.9\;IU$) in high AMH group (p<0.001). There was no significant difference in fertilization rates and pregnancy rates (23.8%, 34.0%, 37.5%) among the groups. Conclusions: Basal serum AMH level correlated better with the number of retrieved mature oocytes than FSH level, suggesting its usefulness for predicting ovarian response. However, IVF outcome was not significantly different according to the AMH levels. Serum AMH level presented good cut-off value for poor- or hyper-responders, therefore it could be useful in prediction of cycle cancellation, gonadotropin dose, and OHSS risk in IVF cycles.

• Clinical and Experimental Pediatrics
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• v.49 no.3
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• pp.305-311
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• 2006

Purpose : GnRH analogues(GnRHa) are used to treat central precocious puberty(CPP). However, in some patients, the GV decrease is so remarkable that it impairs predicted adult height(PAH); and there fore, the addition of growth hormone(GH) is suggested. We analysed the growth changes during two years and final adult height(FAH) in girls with idiopathic CPP treated with combined therapy, compared with those of girls treated with GnRHa alone. Methods : For the analysis, we classified the patients, who was treated for longer than two years, into three groups depending on the initial PAH and combination of GH; PAH_L, treated with GnRHa and PAH less than midparental height(MPH) - 5 cm. PAH_H, treated with GnRHa and PAH greater than MPH - 5 cm. GnRHa＋GH, combined GH treatment, regardless of PAH before treatment. We analysed the GV and PAH change during the first two years and FAH. Results : In PAH_L, the PAH(SDS) at first year of therapy was significantly increased to $153.5{\pm}6.5cm(-1.4{\pm}1.3)$ from $149.7{\pm}6.4cm(-2.1{\pm}1.3)$ before treatment(P=0.004). In PAH_H, there was no significant increase in PAH during the two years of treatment. During the first year of combination of GH and GnRHa, GV and PAH increased significantly. We observed significant increases in FAH, comparing to the initial PAH in the PAH_L and GnRHa＋GH groups. The height gains(FAH - initial PAH) were significantly higher in the PAH_L and GnRHa＋GH groups than that in the PAH_H group. Conclusion : This study suggests the FAH and height gains are improved in patients, whose predicted adult height before treatment was shorter than those with higher predicted adult height, with the treatment of GnRHa alone or in combination with GH. GH could not improve the final adult height, but compensated the growth in patients whose growth velocity was decelerated by GnRHa alone.