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Biomedical subjects

Jin-Woo Kim

Publications and source records attributed to Jin-Woo Kim.

At least 19 recordsLinked to original sources
PubMed2007

Development of plasmid vector and electroporation condition for gene transfer in sporogenic lactic acid bacterium, Bacillus coagulans.

Bacillus coagulans is a sporogenic lactic acid bacterium that ferments glucose and xylose, major components of plant biomass, a potential feedstock for cellulosic ethanol. The temperature and pH for optimum rate of growth of B. coagulans (50 to 55 degrees C, pH 5.0) are very similar to that of commercially developed fungal cellulases (50 degrees C; pH 4.8). Due to this match, simultaneous saccharification and fermentation (SSF) of cellulose to products by B. coagulans is expected to require less cellulase than needed if the SSF is conducted at a sub-optimal temperature, such as 30 degrees C, the optimum for yeast, the main biocatalyst used by the ethanol industry. To fully exploit B. coagulans as a platform organism, we have developed an electroporation method to transfer plasmid DNA into this genetically recalcitrant bacterium. We also constructed a B. coagulans/E. coli shuttle vector, plasmid pMSR10 that contains the rep region from a native plasmid (pMSR0) present in B. coagulans strain P4-102B. The native plasmid, pMSR0 (6823bp), has 9 ORFs, and replicates by rolling-circle mode of replication. Plasmid pNW33N, developed for Geobacillus stearothermophilus, was also transformed into this host and stably maintained while several other Bacillus/Escherichia coli shuttle vector plasmids were not transformed into B. coagulans. The transformation efficiency of B. coagulans strain P4-102B using the plasmids pNW33N or pMSR10 was about 1.5x10(16) per mole of DNA. The availability of shuttle vectors and an electroporation method is expected to aid in genetic and metabolic engineering of B. coagulans.

Amino Acid Sequence↗
PubMed2006

Insulin secretion and insulin resistance in newly diagnosed, drug naive prediabetes and type 2 diabetes patients with/without metabolic syndrome.

The relationships between insulin secretion and resistance in subjects with newly diagnosed prediabetes (preDM) and type 2 DM according to the presence of metabolic syndrome (MS) were controversial. We performed OGTT on 322 drug naive subjects with a history of hyperglycemia of < or =3 months, and divided into three groups, NGT, preDM (IFG and/or IGT), and T2DM. We also diagnosed these subjects with respect to MS according to ATP III criteria modified by Asia-Pacific guidelines and compared IGI and HOMA-IR. When compare groups stratified by the presence of MS, preDM and T2DM groups with MS showed significantly higher mean HOMA-IR and IGI than those without. When compare groups with respect to glucose tolerance, NGT, preDM, and T2DM subgroups in MS group showed significant higher HOMA-IR and lower IGI according to glucose tolerance. However, NGT, preDM, and T2DM subgroups in non-MS group showed a significant decrease in IGI but no significant difference in HOMA-IR as glucose tolerance worsened. In conclusion, deterioration in IGI and aggravation of HOMA-IR are both important in the primary pathogenesis of diabetes in those with MS. However, IGI deterioration may be the only important factor in the primary pathogenesis of T2DM in the absence of MS.

Adult↗
PubMed2006

Free radical-scavenging delta-lactones from Boletus calopus.

The methanol extracts from the fruiting body of the mushroom Boletus calopus showed free radical-scavenging activity. Bioactivity-guided fractionation of the methanol extracts led to a new hydroxylated calopin named calopin B, along with the known delta-lactones calopin and cyclocalopin A. The structure of the new calopin analogue was elucidated by spectroscopic methods. All compounds showed potent free radical-scavenging activity against superoxide, DPPH, and ABTS radicals with IC (50) values of 1.2 - 5.4 microg/mL.

Agaricales↗
PubMed2006

Optimization of extraction of phenolic compounds from flax shives by pressurized low-polarity water.

Pressurized low-polarity water (PLPW) extraction of phenolic compounds from flax shive was investigated using statistically based optimization and the "one-factor-at-a-time" method. Extraction variables examined using central composite design (CCD) included temperature, flow rate, and NaOH concentration of the extracting water. Extraction of phenolic compounds including p-hydroxybenzaldehyde, vanillic acid, syringic acid, vanillin, acetovanillone, and feruric acid was affected by temperature and NaOH concentration; and extraction of all phenolic compounds, except ferulic acid, increased with temperature and NaOH concentration of the extracting water. Flow rate had little effect on concentration of phenolic compounds at equilibrium, but the extraction rate at the early phase was higher for higher flow rates. The mechanism of PLPW extraction of flax shive phenolics was also investigated using a two-site kinetic model and a thermodynamic model. To determine the extraction mechanism, flow rate was varied from 0.3 to 4.0 mL/min while temperature and NaOH concentration were fixed at 180 degrees C and 0.47 M, respectively. The flow rate tests showed the extraction rates of total phenolic (TP) compounds increased with flow rate and can be described by a thermodynamic model. The results from the thermodynamic model demonstrated that a K(D) value of 30 agreed with the experimental data in the flow rate range of 0.3-4.0 mL/min. When the effect of the three independent variables was evaluated simultaneously using CCD, a maximum TP concentration of 5.8 g/kg of dry flax shive (DFS) was predicted from the combination of a high temperature (230.5 degrees C), a high initial concentration of NaOH (0.63 M), and a low flow rate (0.7 mL/min). Maximum TP concentration of 5.7 g/kg of DFS was obtained from extraction conditions of 180 degrees C, 0.3 or 0.5 mL/min, and 0.47 M NaOH at equilibrium. A second-order regression model generated by CCD predicted a maximum TP concentration of 5.8 g/kg of DFS under the same extraction conditions, which is well matched with the results from experimental data.

Flax↗
PubMed2006

New approach to the immobilization of glucose oxidase on non-porous silica microspheres functionalized by (3-aminopropyl)trimethoxysilane (APTMS).

The immobilization and encapsulation of glucose oxidase (GOD) onto the mesoporous and the non-porous silica spheres prepared by co-condensation of tetraethylorthosilicate (TEOS) and (3-aminopropyl)trimethoxysilane (APTMS) in the water-in-oil (W/O) emulsion system were studied. The terminal amine group was used as the important functionality for GOD immobilization on the silica substrate. When only TEOS is used as a silica source, the disordered mesoporous silica microspheres are obtained. As the molar ratio of APTMS to TEOS (R(AT)) increases, the surface area and pore volume of the silica particles measured by nitrogen adsorption and desorption method and SEM decrease rapidly. Particularly, the largest change of the surface morphology is observed between R(AT)=0.20 and R(AT)=0.25. The amount and the adsorption time of immobilized enzyme were measured by UV spectroscopy. About 20wt% of GOD was immobilized into the silica substrates above R(AT)=0.60 and was completely adsorbed into the substrate of R(AT)=0.80 with lapse of 4h after addition. In the measurement of the thermal stability, GOD dissolved in buffer solution loses nearly all of its activity after 30 min at 65 degrees C. In contrast, GOD immobilized on the surface-modified silica particles still retains about 90% of its activity after the same treatment. At this temperature, the immobilized glucose oxidase retained half of its initial activity after 4h. It is shown that the suitable usage of functionalizing agent like APTMS as well as the control of surface morphology is very important on the immobilization of enzyme.

Enzymes, Immobilized↗
PubMed2006

Biodegradation of pentyl amine and aniline from petrochemical wastewater.

The objectives of the project were to isolate a bacterial strain capable of degrading pentyl amine and aniline and to define the optimal pentyl amine and aniline degradation conditions for this bacterial strain. The bacterial strain was isolated from activated sludge obtained from a Northeastern China treatment facility for petrochemical wastewater rich in pentyl amine and aniline. Once the strain was isolated, five triplicate (5) batch tests were used to establish the conditions for maximum pentyl amine and aniline degradation, by varying one at a time the following five factors: temperature, pH, reaction time, pollutant concentrations and aeration rate. In a final test, oil refinery sludge was inoculated with the strain and tested for the degradation of pentyl amine and aniline under optimal conditions, while observing the degradation pathway of pentyl amine and aniline. The isolated strain, PN1001, is a member of the Pseudomonas species and it was capable of degrading pentyl amine and aniline. The optimal reactor conditions for the degradation of a mixture of pentyl amine and aniline, at a concentration ranging between 150 and 200mg/L, were found to be 30 degrees C at a pH of 7.0, under a reaction time of 24h and a maximum solution dissolved oxygen level of 6 mgO(2)/L. Under such conditions, the strain PN1001 degraded 93% and 89% of the pentyl amine and aniline, respectively, aniline being more toxic and demonstrating a more complex degradation pathway. The strain PN1001 degraded more contaminants when both were present because of the pi and sigma electron cloud coordination functions of aniline and pentyl amine, respectively, presumed to reduce the toxic effect of aniline. Once inoculated with the strain, oil refinery sludge degraded 93% and 88% of the pentyl amine and aniline, compared to the strain alone which degraded 72% and 82%, likely because of the sludge's buffering effect against the toxic environment.

Amines↗
PubMed2005

Elevated cAMP level attenuates 2-deoxy-d-ribose-induced oxidative damage in pancreatic beta-cells.

Glucose toxicity to pancreatic beta-cells is defined as irreversible beta-cell damage, including apoptosis, caused by chronic exposure to high glucose levels in type 2 diabetes. Oxidative stress is an important mechanism for glucose toxicity to pancreatic beta-cells. Reducing sugars produce reactive oxygen species through autoxidation and protein glycosylation. 2-Deoxy-d-ribose (dRib) is a reducing sugar with high reactivity. We investigated whether cAMP-stimulating agents could protect beta-cells from dRib-induced oxidative damage. HIT-T15 cells were cultured with various concentrations of dRib for 24 h. We measured cell survival, intracellular cAMP and H2O2 levels, and apoptosis. dRib decreased cell survival in a dose- and time-dependent manner and markedly increased intracellular H2O2 levels and apoptosis. N-Acetyl-l-cysteine decreased dRib-induced rises in intracellular H2O2 and apoptosis to control levels. Forskolin, IBMX, and dbcAMP markedly elevated intracellular cAMP levels and significantly attenuated dRib-induced cytotoxicity and apoptosis, but had no influence on the dRib-induced rise in intracellular H2O2 levels. These results demonstrate that dRib produced oxidative stress and apoptosis in pancreatic beta-cells and that elevated intracellular cAMP levels reduced dRib-induced damage, independent of reactive oxygen species metabolism.

Animals↗
PubMed2005

Differentiation of endothelial cells from human umbilical cord blood AC133-CD14+ cells.

Endothelial progenitor cells (EPCs) participate in neovascularization and are consistent with postnatal vasculogenesis. In vitro, they differentiate into endothelial cells (ECs). Prior reports have suggested that circulating human AC133(+) cells have the capacity to differentiate into ECs as progenitor cells. However, recent studies have demonstrated that circulating CD34(-)CD14(+) cells also have EPC-like properties in vitro and in vivo. We tested whether AC133(-)CD14(+) cells from human umbilical cord blood (HUCB) have the potential to differentiate into ECs. The AC133(-)CD14(+) cells were isolated from HUCB by magnetic bead selection and cultured on fibronectin-coated six-well trays in M199 medium supplemented with fetal bovine serum (FBS), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and insulin growth factor (IGF-1). The AC133(-)CD14(+) cells adhered slightly within 1 day of culture and subsequently underwent a distinct process of morphological transformation to spindle-shaped cells that sprouted from the edge of the cell clusters. After 14 days, the cells formed cord- and tubular-like structures. The AC133(-)CD14(+) cells showed a strong increase in the endothelial marker P1H12 over time, whereas CD14 decreased, and CD45 did not change, respectively. In addition, the cells expressed endothelial markers von Willebrand's factor (vWF), platelet/endothelial cell adhesion molecule-1 (PECAM-1), vascular endothelial growth factor receptor-1 (VEGFR-1)/Flt-1, VEGFR-2/Flk-1, eNOS, and VE-cadherin, but did not express Tie-2 after 7 days of culture. The present data indicate that AC133(-)CD14(+) cells from HUCB are able to develop endothelial phenotype with expression of endothelial-specific surface markers and even form cord- and tubular-like structures in vitro as progenitor cells.

AC133 Antigen↗
PubMed2005

Effects of Aralia continentalis on hyperalgesia with peripheral inflammation.

This study aimed to determine the antinociceptive effect of Aralia continentalis extract (AC) on Freund's adjuvant-induced arthritis in rats. Adult Sprague-Dawley rats received an injection of complete Freund's adjuvant (CFA) into the articular cavity of the ankle joint, and then antinociceptive behaviors and spinal Fos expression were examined. AC was found to suppress significantly nociceptive behaviors caused by CFA injection. In addition, it also decreased adjuvant-induced Fos expression in the lumbar spinal cord induced by CFA. In conclusion, this study showed that AC produced significant antinociceptive effects on CFA-induced arthritis in rats, and it is suggested that AC is recommended to alleviate the arthritis-related symptoms in humans.

Administration, Oral↗
PubMed2005

Effect of surfactant alkyl chain length on soil cadmium desorption using surfactant/ligand systems.

The effect of surfactant alkyl chain length on soil Cd desorption was studied using nonionic surfactants of polyethylene oxide (PEO) of PEO chain lengths of 7.5 (Triton X-114), 9.5 (Triton X-100), 30 (Triton X-305), or 40 units (Triton X-405) in combination with the I- ligand. Triplicate 1 g soil samples were equilibrated with 15 ml of surfactant-ligand mixture, at concentrations of 0.025, 0.50 or 0.10, and 0.0, 0.168 or 0.336 mol/l, respectively. After shaking the samples for 24 h, the supernatant fraction was analyzed for Cd content to determine the percent of Cd desorbed from the soil. After five successive washings, 53%, 40% and 25% of Cd had been desorbed by 0.025, 0.050 or 0.10 mol/l of Triton X-114, respectively, in the presence of 0.336 mol/l of I-, whereas with the same conditions, Triton X-100 desorbed 61%, 57% and 56% Cd and either Triton X-305 or Triton X-405 desorbed 51, 40 and 14 to 16% Cd. The most efficient Cd desorption was obtained using 0.025 mol/l Triton X-100 in admixture with 0.336 mol/l I-. Increased surfactant concentration was detrimental to Cd desorption consistent with a process that blocked ligand access to the soil particle surface. After 5 washings,the cumulative cadmium desorption decreased with increasing surfactant alkyl chain length, indicating that the metal-ligand complexes are preferably stabilized by the micelles' hydrophobic octyl phenyl (OP) group rather than by the hydrophilic PEO group. In the absence of ligand, the surfactants alone desorbed less than 1% Cd from the contaminated soil, suggesting that the ligand, rather than the surfactant, extracts the metal, to be subsequently stabilized within the surfactant micelles.

Cadmium↗
PubMed2004

Inhibition of cytochrome P450 activities by oleanolic acid and ursolic acid in human liver microsomes.

Oleanolic acid (OA) and ursolic acid (UA), triterpene acids having numerous pharmacological activities including anti-inflammatory, anti-cancer, and hepato-protective effects, were tested for their ability to modulate the activities of several cytochrome P450 (CYP) enzymes using human liver microsomes. OA competitively inhibited CYP1A2-catalyzed phenacetin O-deethylation and CYP3A4-catalyzed midazolam 1-hydroxylation, the major human drug metabolizing CYPs, with IC50 (Ki) values of 143.5 (74.2) microM and 78.9 (41.0) microM, respectively. UA competitively inhibited CYP2C19-catalyzed S-mephenytoin 4'-hydroxylation with an IC50 (Ki) value of 119.7 (80.3) microM. However, other CYPs tested showed no or weak inhibition by both OA and UA. The present study demonstrates that OA and UA have inhibitory effects on CYP isoforms using human liver microsomes. It is thus likely that consumption of herbal medicines containing OA or UA, or administration of OA or UA, can cause drug interactions in humans when used concomitantly with drugs that are metabolized primarily by CYP isoforms. In addition, it appears that the inhibitory effect of OA on CYP1A2 is, in part, related to its anti-inflammatory and anticancer activities.

Chromatography, High Pressure Liquid↗
PubMed2004

X-chromosome inactivation patterns in Korean women with idiopathic recurrent spontaneous abortion.

Recurrent spontaneous abortion (RSA) defines as two or more consecutive losses at < or = 20 weeks of gestation and affects an estimated 1 of every 100 couples wishing to have children. However, it remains a poorly understood phenomenon. Recent reports observed a significant association between highly skewed X chromosome and RSA, supporting that X chromosome inactivation might be an important and previously unknown cause of RSA. X-inactivation pattern, using polymeric X-linked women with idiopathic RSA and 80 control subjects with a single successful pregnancy and no history of spontaneous abortion. The ratio of heterozygotes was 68.2% (45/66) in women with RSA and 67.5% (54/80) in control group. Among 45 informative RSA cases, only 1 (2.2%) woman showed extreme skewed X inactivation (> or = 90%) and 4 (8.9%) had mild skewed inactivation (> or = 85%). In 54 heterozygous control subjects, 5 (9.3%) women showed extreme skewed X inactivation and 7 (13.0%) had mild one. The frequency of skewed X inactivation between RSA patients and control group was not significantly different (p>0.05). This finding suggests that skewed x chromosome be not associated with unexplained RSA patients.

Abortion, Habitual↗
PubMed2004

Maternal serum levels of VCAM-1, ICAM-1 and E-selectin in preeclampsia.

Endothelial dysfunction is thought to be a central pathogenic feature in preeclampsia on the basis of elevated adhesion molecules. The aim of the present study was to compare the levels of soluble vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1 (sICAM-1) and E-selectin (sE-selectin) in sera of normal and preeclamptic pregnancies. We studied the serum levels of sVCAM-1, sICAM-1 and sE-selectin in normal pregnant women (n=63), mild preeclampsia (n=33) and severe preeclampsia (n=82). Concentrations of soluble adhesion molecules were determined with enzyme-linked immunoassay (ELISA). Serum concentrations of sVCAM-1 were significantly higher in both mild (p=0.004) and severe preeclampsia (p=0.000) than normal pregnancy. There were also significant differences in sVCAM- 1 levels between mild and severe preeclampsia (p=0.002). sICAM-1 levels of severe preeclampsia were statistically different from those of normal pregnancy (p=0.038). Levels of sE-selectin were elevated in both mild (p=0.011) and severe preeclampsia (p=0.000) compared to normal pregnancy, but no statistical difference between the mild and severe preeclampsia (p=0.345). These results suggest that all three soluble adhesion molecules are increased in severe preeclampsia, and sVCAM-1 among them may be useful in predicting the severity of preeclampsia.

Adult↗
PubMed2004

Delayed primary repair of perforated epiphrenic diverticulum.

A 68-yr-old man complaining of sudden, postprandial chest pain visited the emergency room. His symptom had been aggravated during the preceding two days. Upper gastrointestinal contrast study with gastrographin showed leakage of dye from the epiphrenic diverticulum in the lower third of the esophagus. The primary repair was urgently carried out. Upper gastrointestinal contrast study 14 days after operation revealed an esophageal leakage which was small and confined. The patient was managed with conservative treatments such as intravenous hyperalimentation and broad-spectrum antibiotics. Forty-two days after the operation, a gastrographin swallow study showed the absence of leaks. This is the first reported case of a perforated epiphrenic esophageal diverticulum repaired by delayed primary repair in Korea.

Aged↗
PubMed2004

Simultaneous soil Cd and PCB decontamination using a surfactant/ligand solution.

The simultaneous desorption of Cd and PCBs, from a contaminated soil, was investigated using a surfactant/ligand solution. The test surfactants were combinations of a nonionic surfactant [polyethylene oxide (PEO) of chain length 7.5 (Triton X-114), 9.5 (Triton X-100), 30 (Triton X-305), or 40 units (Triton X-405)], with iodide (I-). Triplicate 1 g soil samples were equilibrated, during 24h, with 15 mL of surfactant/ligand solution, at 0.025 or 0.50 and 0.0, 0.168, or 0.336 mol L(-1), respectively. The supernatant fraction was then separated from the particulates by centrifugation and analyzed for Cd to determine Cd desorption efficiency. After five consecutive washings, the treated soil samples were analyzed for PCB content to determine the desorption efficiency of this class of toxicant. Desorption of Cd increased with both increasing ligand concentration and decreasing surfactant chain length and concentration. The maximum Cd desorption efficiency (61%), was obtained with Triton X-100 at 0.025 mol L(-1), in the presence of I at 0.336 mol L(-1). After 5 successive washings, virtually quantitative PCB desorption (below limits of detection for tetra-, penta-, and hexachloro biphenyl compounds) had been achieved with most of surfactant/ligand combinations. Maximum desorption efficiency was achieved using either shorter chain length surfactant (n = 7.5 or 9.5) in combination with a higher ligand concentration, or using longer chain length surfactants (n = 30 and 40) with a lower ligand concentration. Thus, heavy metals and PCBs can be desorbed simultaneously from a contaminated soil with the same washing reagents, namely a surfactant-ligand combination. The optimum surfactant-ligand combination for the simultaneous desorption of both heavy metals and PCBs was a short chain length (n = 7.5 or 9.5) surfactant at low concentration admixed with 0.336 mol L(-1) I-.

Adsorption↗
PubMed2003

Harpagophytum procumbens suppresses lipopolysaccharide-stimulated expressions of cyclooxygenase-2 and inducible nitric oxide synthase in fibroblast cell line L929.

Harpagophytum procumbens (Pedaliaceae) has been used for the treatment of pain and arthritis. The effect of Harpagophytum procumbens against lipopolysaccharide-induced inflammation was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, reverse transcription-polymerase chain reaction, prostaglandin E(2) (PGE(2)) immunoassay, and nitric oxide detection on mouse fibroblast cell line L929. The aqueous extract of Harpagophytum procumbens was shown to suppress PGE(2) synthesis and nitric oxide production by inhibiting lipopolysaccharide-stimulated enhancement of the cyclooxygenase-2 and inducible nitric oxide synthase (iNOS) mRNAs expressions in L929 cells. These results suggest that Harpagophytum procumbens exerts anti-inflammatory and analgesic effects probably by suppressing cyclooxygenase-2 and iNOS expressions.

Animals↗
PubMed2003

De novo chromosomal aberrations in the fetus; genetic counseling and clinical outcome.

The aim of this study was to examine the incidence and clinical outcome of de novo chromosomal aberrations retrospectively and provide useful data for genetic counseling in the prenatal cytogenetic diagnosis. We found 17 cases of de novo chromosomal aberrations in 5501 cases of prenatal cytogenetic analysis and reviewed the karyotype, further study, medical records, fetal ultrasound findings and clinical outcomes. Out of the 17 de novo chromosomal aberrations, 5 had balanced reciprocal translocations and 12 had unbalanced translocations characterized as deletion, addition, or marker. In the case of the five balanced reciprocal translocations, 3 cases without abnormal ultrasound findings were carried to term after comprehensive genetic counseling. Neonates were phenotypically normal and clinical examinations were normal. Two cases with abnormal ultrasound findings were terminated therapeutically. Twelve cases of unbalanced translocations were terminated except one case with a mosaic marker chromosome. High resolution fetal ultrasound and detailed cytogenetic and molecular study will be adjunctive tools for predicting the karyotype/phenotype correlations of fetuses with de novo chromosomal aberrations, although they have limitation to find all phenotypic effects.

Chromosome Aberrations↗