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Dae Young Kim

Publications and source records attributed to Dae Young Kim.

At least 19 recordsLinked to original sources
PubMed2006

Cell cycle regulators control centrosome elimination during oogenesis in Caenorhabditis elegans.

In many animals, the bipolar spindle of the first zygotic division is established after the contribution of centrioles by the sperm at fertilization. To avoid the formation of a multipolar spindle in the zygote, centrosomes are eliminated during oogenesis in most organisms, although the mechanism of this selective elimination is poorly understood. We show that cki-2, a Caenorhabditis elegans cyclin-dependent kinase (Cdk) inhibitor, is required for their appropriate elimination during oogenesis. In the absence of cki-2, embryos have supernumerary centrosomes and form multipolar spindles that result in severe aneuploidy after anaphase of the first division. Moreover, we demonstrate that this defect can be suppressed by reducing cyclin E or Cdk2 levels. This implies that the proper regulation of a cyclin E-Cdk complex by cki-2 is required for the elimination of the centrosome that occurs before or during oogenesis to ensure the assembly of a bipolar spindle in the C. elegans zygote.

Animals↗
PubMed2006

Release of heat shock protein 70 (Hsp70) and the effects of extracellular Hsp70 on matric metalloproteinase-9 expression in human monocytic U937 cells.

Heat shock protein 70 (Hsp70) release and its effects on pro-inflammatory cytokine production have been controversial. In this study, we investigated whether Hsp70 could be released from monocytes and activates matrix metalloproteinase-9 (MMP-9) gene expression. Hsp70 overexpression in human monocytic cell line U937 was found to increase PMA-induced MMP-9 expression and enhance cell motility. Hsp70 cDNA transfectants released Hsp70 protein into culture supernatants, and a part of released Hsp70 subsequently was bound to the surface of U937 cells. Addition of culture medium containing the extracelluar Hsp70 led to an increase not only in proMMP-9 secretion, but also the invasiveness of U937 cells through Matrigel or human umbilical vascular endothelial cells (HUVEC) in vitro. Immunodepletion of Hsp70 abolished its effect on MMP-9 expression. The released Hsp70 activated nuclear factor kappa B (NF-kappaB) and activating protein-1 (AP-1), which led to the activation of MMP-9 transcription. Taken together, these results suggest that extracellular Hsp70 induces the expression of MMP-9 gene through activation of NF-KappaB and AP-1.

Cell Movement↗
PubMed2006

Appropriate waist circumference cutoff points for central obesity in Korean adults.

BACKGROUND: The International Diabetes Federation consensus recently proposed a new definition for the diagnosis of metabolic syndrome, incorporating ethnically specific waist circumference (WC) cutoff points. OBJECTIVE: We investigated the ethnically appropriate WC cutoff values for central obesity in Korean adults to predict increased risk of elevated triacylglycerol, reduced HDL cholesterol, elevated blood pressure, elevated fasting plasma glucose, or two or more of these factors. DESIGN: We used data from 6561 adults, aged 20-80 years, who participated in the Korean Health and Nutritional Examination Survey of 1998, a cross-sectional health survey of a nationally representative sample of Koreans. RESULTS: Based on the receiver operating characteristic curve analysis, the WC value for predicting metabolic risk factors in Koreans was about 85 cm for men and 80 cm for women. The odds ratio for the risk of two or more metabolic risk factors increased abruptly in men with WC >or= 90 cm and women with WC >or= 85 cm. The 80th percentile for WC in the Korean population was 90 cm for men and 86.5 cm for women. Thus, the appropriate WC cutoff point for central obesity in Koreans was determined to be 90 cm for men and 85 cm for women. CONCLUSIONS: Based on our criteria, the prevalence of central obesity was 19.8% in Korean men and 24.5% in Korean women. These findings suggest the applicability of ethnically specific cutoff points for WC in assessing central obesity.

Adult↗
PubMed2006

[Survival analysis for patients with hepatocellular carcinoma according to stage, liver function and treatment modalities].

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) is 3rd leading cause of cancer in Korea and the prognosis for HCC patients is poor. For assessing the present treatment outcome, this study analyzed the three-year survival rate (3-YSR) and the prognostic factors for patients with HCC in Korea. METHODS: Between November 2000 and December 2003, 905 patients with HCC who were diagnosed and treated at the National Cancer Center Korea were enrolled in this study. The clinical variables, tumor characteristics and survival periods were analyzed. RESULTS: The mean age of all patients was 56.2+/-10.3 years and 732 (80.9%) patients were male (M:F=4.2:1). 508 (56.1%) patients died and the median survival period was 15.3 months. The overall 3-YSR of the patients with modified UICC stage I, II, III, IVa and IVb were 67.4%, 65.2%, 30.7%, 9.0% and 5.0%, respectively. The modified UICC stage could not differentiate stage I from II, and stage IVa from IVb, on the 3-YSR. The 3-YSR of the Child-Pugh class A patients with modified UICC stage I or II was 85.4% by surgical resection and it was 69.6% by transcatheter chemoembolization (TACE), respectively (P= .461), and those values for patients with stage III were 49.2% and 36.8%, respectively (P=.081). As compared with systemic chemotherapy or conservative therapy, TACE increased the survival rate more for the Child-Pugh class A patients with stage IV. The independent prognostic factors were serum AFP, portal vein thrombosis, the Child-Pugh classification and the stage of HCC. CONCLUSIONS: This follow-up study will be helpful in assessing the results of treatments for HCC and it will provide data for the establishment of a more effective treatment strategy.

Aged↗
PubMed2005

Two-photon absorption properties of 2,6-bis(styryl)anthracene derivatives: effects of donor-acceptor substituents and the pi center.

A series of 2,6- and 2,7-bis(styryl)anthracene derivatives with the donors at the styryl group and acceptors at the 9,10-positions have been synthesized, and their two-photon cross sections (Phidelta(max)) were determined. These compounds exhibit a peak two-photon absorptivity (delta(max)) in the range of 700-2500 GM at 780-1030 nm. Values of lambda(max) and Stokes shifts increase as the acceptor is changed to a stronger one. There is also a parallel increase in lambda(2)max and delta(max) with the same variation of the chromophore structure. Both lambda (2)(max)and Phidelta(max) have been optimized by introducing donor-substituted styryl groups at the 2,6-positions and p-cyanophenyl groups at the 9,10-positions, respectively. The effect of a pi center on the two-photon absorption properties has been assessed by comparing the existing data for a variety of D-pi-D derivatives.

Journal Article↗
PubMed2005

Catalytic enantioselective fluorination and amination of beta-keto phosphonates catalyzed by chiral palladium complexes.

[reaction: see text] The catalytic enantioselective fluorination and amination of beta-keto phosphonates catalyzed by chiral palladium complexes is described. Treatment of beta-keto phosphonates with N-fluorobenzenesulfonimide (NFSI) as electrophilic fluorinating reagent and diethyl azodicarboxylate (DEAD) as electrophilic amination reagent under mild reaction conditions afforded the corresponding alpha-substituted beta-keto phosphonates in moderate to excellent yields with excellent enantiomeric excesses.

Journal Article↗
PubMed2005

Naturally occurring eastern equine encephalitis in a Hampshire wether.

Eastern equine encephalitis (EEE) was diagnosed (postmortem) in a sheep with clinical signs attributable to a central nervous system disease. The sheep was febrile and initially had front limb incoordination, which progressed to paralysis of both front and hind limbs during a course of 2 days. The sheep maintained an alert attitude with the ability to eat up to the time of euthanasia. The only clinical pathologic abnormalities were neutrophilia and lymphopenia without appreciable leukocytosis, a moderate hyperglycemia, and an elevated creatine kinase. Treatment included hydrotherapy for lowering body temperature, intravenous fluids, thiamine hydrochloride, tetanus antitoxin, antibiotics, and corticosteroids. The only gross lesion at the time of necropsy was a wet glistening surface of the brain (leptomeninges). Microscopically, there was severe nonsuppurative meningoencephalitis, poliomyelitis, and polyradiculoneuritis with mild multifocal neutrophilic infiltration. The EEE virus was isolated from the brain, and subsequent fluorescent antibody testing for EEE was positive on cell culture.

Animals↗
PubMed2004

Role of messenger RNA expression of platelet activating factor and its receptor in porcine in vitro-fertilized and cloned embryo development.

Platelet activating factor (PAF) is known as an autocrine growth/survival factor in mammalian preimplantation embryos. This study investigated the expression of porcine PAF receptor (PAFr) mRNA and its role in porcine in vitro fertilized (IVF) or somatic cell nuclear transfer (SCNT) embryo development. The expression of PAFr mRNA in IVF or SCNT blastocysts was shown by reverse transcription-polymerase chain reaction (RT-PCR) and Southern blot analysis. Semiquantitative RT-PCR and Southern blot analysis demonstrated that PAFr mRNA was expressed during preimplantation embryo development, it was highly expressed through the 2-cell to 8-cell embryo stage, and it decreased at the morula stage. PAFr mRNA expression was detected steadily in IVF embryos, whereas it was varied at the 2-cell, 4-cell, and blastocyst stages in SCNT embryos. To determine the role of PAF in IVF and SCNT embryo development, embryos were cultured in North Carolina State University (NCSU)-23 medium supplemented with different concentrations of PAF (0, 0.037, 0.37, 3.72, or 37.2 nM). The PAF supplement significantly increased the rate of blastocyst formation in SCNT embryos, but not in IVF embryos. The PAF supplement for the entire 168 h of culture showed significantly higher blastocyst formation in SCNT embryos. Upregulation of PAFr mRNA by PAF in SCNT embryos indicated that the embryotrophic effect of PAF was mediated through its functional receptors in SCNT embryos. In conclusion, the present study demonstrated that PAFr mRNA was expressed in porcine IVF and SCNT embryos, and that PAF supplement improved the developmental competence of SCNT embryos through its specific receptors.

Animals↗
PubMed2004

Triphenylamine derivatives with large two-photon cross-sections.

[structure: see text] Triphenylamine derivatives have been synthesized and shown to exhibit large two-photon cross-sections at a wide range of wavelengths and the largest value measured by fs Z-scan experiment. Moreover, a linear relationship is noted between the two-photon cross-sections measured by ns fluorescence and fs Z-scan methods.

Journal Article↗
PubMed2004

A surgical approach for earlobe keloid: keloid fillet flap.

Earlobe keloid can form after cosmetic ear piercing, trauma, or burns, and it poses several difficulties in treatment and distinctive cosmetic implications. Treatment methods for earlobe keloids include both surgical and nonsurgical methods. After excision of the earlobe keloid, healing by secondary intention, primary suture, skin graft, or local flap has revealed some disadvantages. The authors approached this problem with a new excision and covering method. The surgery was performed under local anesthesia. Skin over the keloid was dissected from the keloid mass as a flap, which they termed a "keloid fillet flap," and the keloid mass was completely removed. Subcutaneous sutures were not used, and the keloid fillet flaps were closed with 6-0 nylon sutures after trimming. Other intraoperative or postoperative preventive procedures, such as steroid injection, pressure device, or irradiation, were not applied primarily. In the period from May of 1999 to October of 2000, nine earlobe keloids in eight patients were treated with this protocol. One patient had bilateral keloids. Of the eight patients, there were six women and two men, ranging in age from 21 to 61 years (mean age, 28.5 years). The causes of keloids were ear piercing in six cases and trauma in three cases. The largest lesion was 3 cm in its greatest dimension, and the smallest was 1.5 cm (mean, 2.3 cm). All flaps survived completely. There were four cases of recurrence. Seven cases, including two recurrences, showed good results. The authors believe the recurrence of earlobe keloid was closely related to the method for coverage of the defect after its surgical excision, and the "5 As and one B" (Asepsis, Atraumatic technique, Absence of raw surface, Avoidance of tension, Accurate approximation of wound margin, and complete Bleeding control) are important factors in reducing the recurrence rate of earlobe keloids in surgical excision. The authors' protocol is very effective in closing the defect after surgical excision of earlobe keloids and offers many advantages over other surgical approaches. The recurrence rate of earlobe keloid may be lower than in their results if other intraoperative and postoperative treatment procedures are combined with their protocol.

Adult↗
PubMed2004

Assessment of apoptosis in epidermal lamellar cells in clinically normal horses and those with laminitis.

OBJECTIVE: To determine and compare the number, type, location, and distribution of apoptotic epidermal cells in the laminae of clinically normal horses and horses with laminitis. SAMPLE POPULATION: Formalin-fixed samples of digital lamellar tissue from 47 horses (including clinically normal horses [controls; n = 7], horses with acute [4] and chronic [7] naturally acquired laminitis, and horses with black walnut extract-induced [11] or carbohydrate overload-induced [18] laminitis). PROCEDURE: Blocks of paraffin-embedded lamellar tissues were stained for DNA fragmentation with the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) technique. Differential immunohistochemical staining for caspases 3 and 14 were used to confirm apoptosis. RESULTS: The number of TUNEL-positive epidermal cells per 0.1 mm of primary laminae was significantly greater in the acute laminitis group than in the other groups. In the acute laminitis group, there were 17 and 1,025 times as many TUNEL-positive basal layer cells and keratinocytes, respectively, compared with the control group. Apoptosis of TUNEL-positive basal layer cells was confirmed by results of caspase 3 immunohistochemical staining. The TUNEL-positive keratinocytes did not stain for caspases 3 or 14. CONCLUSIONS AND CLINICAL RELEVANCE: The large number of apoptotic basal layer cells detected in the lamellar tissue of horses with acute naturally acquired laminitis suggests that apoptosis may be important in the development of acute laminitis. The role of the large number of TUNEL-positive keratinocytes detected in the interface of primary and secondary epidermal laminae of horses with acute laminitis remains to be elucidated.

Animals↗
PubMed2003

Resurfacing of a totally degloved hand using thin perforator-based cutaneous free flaps.

Resurfacing after a total degloving injury to the hand is one of the most difficult management problems in hand surgery. Although there are many methods of managing this type of injury that preserve functions and lessen deformities, none provides a satisfactory solution to this problem. The authors resurfaced a totally degloved hand using extremely thin and broad perforator-based cutaneous free flaps, and the donor defects were covered with split-thickness skin grafts. The postoperative course was uneventful, the flaps survived completely, and the grafts took without loss. Several minor operations, including interdigitation, defatting, and the formation of palmar and digital creases, were required to obtain the final appearance and function of the hand. Eighteen months after the initial operation, the patient could pick up a bean with a pair of chopsticks. Sensation was satisfactory in the palm 20 months after the initial operation, as evidenced by 10 mm of static two-point discrimination. To reconstruct a total and complete skin defect of the hand, the authors recommend that thin perforator-based cutaneous free flaps be an initial consideration.

Adult↗
PubMed2003

Correction of inverted nipple: an alternative method using two triangular areolar dermal flaps.

Inverted nipple, which is defined as a nipple located on a plane lower than the areola, presents both functional and cosmetic problems. It is a source of repeated irritation and inflammation, and interferes with nursing. In addition, its abnormal appearance may cause psychological distress. Inverted nipples are congenital or acquired, and are classified as the umbilicated and invaginated types or divided into 3 groups (grades 1, 2, and 3). With consideration of its underlying pathophysiologic components and severity, various surgical procedures have been proposed. For correcting the inverted nipple, the authors introduce an alternative, simple method using 2 triangular areolar dermal flaps. Compared with other methods using triangular areolar dermal flaps, each triangle is approximately 1 mm shorter than the diameter of the nipple, and the deepithelialized areolar dermal flaps are lodged at the slit in the bundle of the lactiferous ducts in the grade 2 inverted nipple. From August 2000 to December 2001, 11 patients (16 nipples) were treated. Five patients had bilateral inverted nipples. Patient age at operation ranged from 18 to 31 years (mean age, 27 years). All nipples were congenital and they had no previous operation. Thirteen nipples were grade 2 and 3 were grade 3 according to the classification of inverted nipple by Han and Hong. The mean follow-up period was 8.7 months (range, 3-12 months). Follow-up examinations revealed no evidence of recurrence of inversion. There was no complication associated with surgery, such as infection, hematoma, permanent sensory disturbance, or nipple necrosis. The resulting scars were minimal. All patients were satisfied with their results. The authors conclude that their procedure is reliable, preserves the lactiferous ducts in grade 2 inverted nipple, requires no special postoperative care, and leaves minimal scars and no recurrence of inversion. This technique can be applied to any type of inverted nipple as a primary surgical procedure.

Adolescent↗
PubMed2002

Catalytic enantioselective fluorination of beta-keto esters by phase-transfer catalysis using chiral quaternary ammonium salts.

[reaction: see text] The catalytic enantioselective electrophilic fluorination promoted by quaternary ammonium salt from cinchonine as a phase-transfer catalyst is described. Treatment of beta-keto esters with N-fluorobenzenesulfonimide as the fluorine source under mild reaction conditions afforded the corresponding alpha-fluoro beta-keto esters in exellent yields with good to moderate enantiomeric excesses

Catalysis↗