• Journal of the Institute of Electronics Engineers of Korea SC
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• v.42 no.1
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• pp.39-45
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• 2005

As a basic research for the development of a non-invasive blood glucose sensor using millimeter waves, we have presented a method for measuring the dielectric properties of high loss dielectrics, based on the reflection method, and investigated the variation of the dielectric properties of glucose-water and glucose -0.9% NaCl solutions in the 10～90 GHz range. In the proposed method, a minimal reflection condition is formed by placing a specially-chosen low-loss plane-parallel plate in front of a high-loss medium under test at a given frequency range. Using the minimal power reflection coefficient and the corresponding frequency at this condition, tile dielectric properties of the medium can be determined. The measured results on pure water have shown the adequacy of the proposed method. The measured results on glucose-water and glucose -0.9% NaCl solutions in the 10～90 GHz range showed that the variations of the dielectric properties of glucose solutions according to the change of their glucose concentration were maximum in the 30～45 GHz range. From these facts we concluded that the variation of about 3 mole/L in the glucose solutions must be distinguished With the measurement accuracies of ±0.1 dB and ±0.01 GHz.

• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.263-268
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• 1989

To maximize the performance of recombinant cell fermentation process through optimizing environmental conditions, the production of invertase from recombinant Saccharomyces cerebisiae Containing SUC2 gene was studied as a model. The recombinant cells showed biphasic growth on glucose. Since the promoter of the SUC2 is regulated by the concentration of glucose in the medium, expression of invertase by recombinant yeast began when the glucose concentration decreased in a range of 0.25-0.4 g/L during the batch culture. Plasmid segregation occured frequently during glucose fermentation, and infrequently during ethanol oxidation. A rapid appearance of invertase activity with glucose was observed under nonaerated condition, and the maximum specific invertase activity was about 1.5 times as high as under aerobic condition, In fed batch culture, when n low level of glucose was continuously supplied to the tormentor after the time of glucose depletion during growth phase, specific and total invertase activity increased about 1.7 and 2.9 fold, respectively, in a batch culture.

• Biomedical Science Letters
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• v.9 no.4
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• pp.177-181
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• 2003

The baculovirus/Spodoptera frugiperda (Sf) cell system has become popular for the production of large amounts of the human erythrocyte glucose transporter, GLUT1, heterologously. However, it was not possible to show that the expressed transporter in insect cells could actually transport glucose. The possible reason for this was that the activity of the endogenous insect glucose transporter was extremely high and so rendered transport activity resulting from the expression of exogenous transporter very difficult to detect. Sf21-AE cells are commonly employed as the host permissive cell line to support the baculovirus AcNPV replication and protein synthesis. The cells grow well on TC-100 medium that contains 0.1 % D-glucose as the major carbon source, strongly suggesting the presence of endogenous glucose transporters. However, unlike the human glucose transporter, very little is known about properties of the endogenous sugar transporter(s) in insect cells. Thus, the uptake of 2-deoxy-D-glucose (2dGlc) by Sf21-AE cells and the inhibition of 2dGlc transport in the insect cells by fructose and cytochalasin B were investigated in the present work. The binding assay of cytochalasin B was also performed, which could be used as a functional assay for the endogenous glucose transporter(s) in the insect cells. Sf21-AE cells were infected with the recombinant virus AcNPV-GT or no virus, at a multiplicity of infection (MOI) of 5. Infected cells were resuspended in PBS plus and minus 300 mM fructose, and plus and minus 20 $\mu$M cytochalasin B for use in transport assays. Uptake was measured at 28$^{\circ}C$ for 1 min, with final concentration of 1 mM deoxy-D-glucose, 2-[1,2-$^3$H]- or glucose, L-[l,$^3$H]-, used at a specific radioactivity of 4 Ci/mol. The results obtained demonstrated that the sugar uptake in uninfected cells was stereospecific, and was strongly inhibited by fructose but only poorly inhibitable by cytochalasin B. It is therefore suggested that the Sf21-AE glucose transporter has very low affinity for cytochalasin B, a potent inhibitor of human erythrocyte glucose transporter.

• Nutrition Research and Practice
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• v.7 no.3
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• pp.166-171
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• 2013

The purpose of this study was to investigate the effects of lotus leaf on hyperglycemia and dyslipidemia in animal model of diabetes. Inhibitory activity of ethanol extract of lotus leaf against yeast ${\alpha}$-glucosidase was measured in vitro. The effect of lotus leaf on the postprandial increase in blood glucose levels was assessed in streptozotocin-induced diabetic rats. A starch solution (1 g/kg) with and without lotus leaf extract (500 mg/kg) was administered to the rats after an overnight fast, and postprandial plasma glucose levels were monitored. Four-week-old db/db mice were fed a basal diet or a diet containing 1% lotus leaf extract for 7 weeks after 1 week of acclimation to study the chronic effect of lotus leaf. After sacrifice, plasma glucose, insulin, triglycerides (TG), total cholesterol (CHOL), high-density lipoprotein (HDL)-CHOL, and blood glycated hemoglobin levels were measured. Lotus leaf extract inhibited ${\alpha}$-glucosidase activity by 37.9%, which was 1.3 times stronger than inhibition by acarbose at a concentration of 0.5 mg/mL in vitro. Oral administration of lotus leaf extract significantly decreased the area under the glucose response curve by 35.1% compared with that in the control group (P < 0.01). Chronic feeding of lotus leaf extract significantly lowered plasma glucose and blood glycated hemoglobin compared with those in the control group. Lotus leaf extract significantly reduced plasma TG and total CHOL and elevated HDL-CHOL levels compared with those in the control group. Therefore, we conclude that lotus leaf is effective for controlling hyperglycemia and dyslipidemia in an animal model of diabetes mellitus.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.4
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• pp.279-285
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• 2017

In this paper, the resonator with a parallel plate capacitor is newly proposed around sub-microwave frequency band and applied to earlobe for non-invasive glucose monitoring the human biological tissue. The capacitor including the earlobe as dielectric material is connected to inductive slot in the ground plane of the microstrip line. Based on the simulation, one port resonator circuit is designed and fabricated as a prototype. Three step glucose concentration levels(0, 250, 500 mg/dL) was tested, and its reflection coefficients($S_{11}$) were measured. Owing to high Q resonator more than 100, resonant frequency shift of about 9 MHz per glucose level of 250 mg/dL has been successfully measured. This proves that the proposed sensor is applicable to a blood glucose sensor.

• The Journal of Korean Physical Therapy
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• v.22 no.6
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• pp.65-70
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• 2010

Purpose: Exercise has been shown to be a simple and economical therapeutic modality that may be considered as an effective aid for diabetic mellitus. For example, exercise training increases insulin sensitivity in type 2 diabetes. But we found no reported of how exercise affect type 1 diabetes. This study investigated the impact of aerobic and graduated treadmill exercise regimens on body weight, glucose and insulin concentrations, lipid profiles, and oxidative stress indicators in rats with streptozotocin (STZ) induced diabetes. Glycosylated hemoglobin ($HbA_{1c}$) was determined as an indicator of glucose control during exercise. Methods: In our study, a total of 40 rats were used. Three groups of 10 rats each were given STZ to induce diabetes. The remaining 10 rats became the normal group. After 28 days we determined biochemical parameters such as glucose, glycosylated hemoglobin ($HbA_{1c}$), insulin concentration, serum total cholesterol (TC), triglycerides (TG), and high-density lipoprotein (HDL). Superoxide dismutase (SOD) and catalase activities were also measured. Results: Concentrations of blood glucose and $HbA_{1c}$ in the moderated exercise groups were significantly decreased after 28 days compared with the control group (p<0.05). There was a significant reduction in serum TC and TG in the experimental groups. The activity of SOD increased significantly by 17.70% and 48.25% respectively. Conclusion: These results indicate that physical training and exercise training affects body weight, fasting blood glucose, $HbA_{1c}$, insulin, lipid profiles, and antioxidant status in rats with streptozotocin-induced diabetes. We suggest that graduated treadmill exercise may have therapeutic, preventative, and protective effects against diabetes mellitusby improving glycemic control, oxidant defenses, and lipid metabolism.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.2
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• pp.78-83
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• 2021

In this study, we prepared NiCo2O4 nanoparticles with large surface area by hydrothermal synthesis. In order to optimize the processing conditions for spinel NiCo2O4 nanoparticles with large surface area, experimental variables including concentration of Ni and Co precursor, reaction time, and temperature for post-heat treatment were evaluated. Optimized conditions for spinel NiCo2O4 with large surface area were [Ni]/[Co] 1:2 ratio, reaction time for 12 h, and post-heat treatment at 400℃. To investigate the feasibility as potential application for glucose sensor, electrochemical tests of the prepared NiCo2O4 nanoparticles in response to glucose was performed, which suggests that the NiCo2O4 can be suitable for a non-enzymatic-based electrochemical glucose sensor based on its high sensitivity and selectivity for glucose detection.

• Journal of Microbiology and Biotechnology
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• v.5 no.5
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• pp.292-296
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• 1995

Production of poly($\beta$-hydroxybutyrate-co-$\beta$-hydroxyvalerate)[poly(HB-co-HV) from glucose and propionic acid was studied in a two-stage fed-batch fermentation using Alcaligenes eutrophus NCIMB 11599. When either glucose became sufficient or the feeding rate of propionic acid decreased, production of poly(HB-co-HV) increased but concomitantly resulted in a reduced fraction of HV. During the copolymer accumulation stage, the specific production rate of hydroxyvalerate (HV) increased up to 0.013 (g-HV/g-RCM/h) but it decreased as propionic acid was accumulated. Control of the propionic acid concentration in the medium, therefore, is considered to be one of the most important operating parameters for production of poly(HB-co-HV) with a higher HV fraction. A high titre of poly(HB-co-HV) (85.6 g/I) with HV fraction of 11.4 mol$%$ could be obtained in 50 h by controlling the propionic acid concentration at 1 to 4 g/I.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.351-354
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• 2001

In this experiment, we tested various nitrogen sources and then culture condition was optimized for industrial applications. The batch culture of Candida magnoliae SR101 grown in a defined medium supplemented with light steep water (LSW) as a sole nitrogen source showed a relatively high yield of erythritol production (53%), which was slightly higher than that using yeast extract as a nitrogen source, while the productivity and cell mass were maintained at similar levels. For the optimization of culture condition, the batch culture was performed. When the concentration of LSW was 65 mL/L in the defined medium containing 250 g/L of glucose, the concentration, yield and productivity of erythritol were 110 g/L, 44%, and 0.66 g/L-hr, respectively. The high yield and comparable productivity obtained with a cheap nitrogen source could be expected as a basis for the mass production of erythritol in the industrial scale.

• Korean Journal of Acupuncture
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• v.20 no.1
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• pp.31-38
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• 2003

Effects of Haenggan($LR_2$) and Chungwan ($CV_{12}$) acupuncture on plasma lipid composition were investigated in rat fed high fat diet. Body weight gain showed a tendency to decrease in acupuncture groups and in acupuncture groups, chungwan acupuncture groups showed a lower values than haenggan acupuncture group. Concentrations of plasma triglyceride, free fatty acids showed a decrease in the acupuncture groups. Concentration of plasma lipoprotein showed a tendency to decrease in acupuncture groups, however in the control group and haenggan group, the values showed no significantly different. Plasma glucose concentration showed a low values than control group, in acupuncture groups, the values showed no significantly different. In plasma cholesterol concentration, total cholesterol and LDL-cholesterol showed a tendency to decrease in acupuncture groups, however the values of LDL-cholesterol showed no significantly different in the control group and haenggan group. HDL-cholesterol concentration showed no significantly different in all treatment groups.