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D G Kim

Publications and source records attributed to D G Kim.

At least 55 records · Page 3Linked to original sources
PubMed1999

Human very-long-chain acyl-CoA synthetase: cloning, topography, and relevance to branched-chain fatty acid metabolism.

Very-long-chain acyl-CoA synthetases (VLCS) activate very-long-chain fatty acids (VLCFA) containing 22 or more carbons to their CoA derivatives. We cloned the human ortholog (hVLCS) of the gene encoding the rat liver enzyme (rVLCS). Both hVLCS and rVLCS contain 620 amino acids, are expressed primarily in liver and kidney, and have a potential peroxisome targeting signal 1 (-LKL) at their carboxy termini. When expressed in COS-1 cells, hVLCS activated the VLCFA lignoceric acid (C24:0), a long-chain fatty acid (C16:0), and two branched-chain fatty acids, phytanic acid and pristanic acid. Immunofluorescence and immunoblot studies localized hVLCS to both peroxisomes and endoplasmic reticulum. In peroxisomes of HepG2 cells, hVLCS was topographically oriented facing the matrix and not the cytoplasm. This orientation, coupled with the observation that hVLCS activates branched-chain fatty acids, suggests that hVLCS could play a role in the intraperoxisomal reactivation of pristanic acid produced via alpha-oxidation of phytanic acid.

Amino Acid Sequence↗
PubMed1999

Down-regulation of insulin-like growth factor binding proteins and growth modulation in hepatoma cells by retinoic acid.

We observed that all-trans-retinoic acid (RA) down-regulated insulin-like growth factor binding proteins (IGFBPs) in cultured human hepatoma cells (Hep 3B, PLC/PRF/5, and Hep G2); therefore, we characterized the role of this down-regulation in cell growth. Treatment with 10 micromol/L RA revealed a rapid decrease in IGFBP-3 within 2 days, and continued treatment with RA for 6 days resulted in a time-dependent stimulation of Hep 3B cell growth. However, RA treatment decreased IGFBP-1 in PLC/PRF/5 cells and in Hep G2 cells, and the growth-stimulatory activity of RA was transient and less prominent, and was finally obliterated in both cell lines. The addition of 5 ng/mL or 50 ng/mL insulin-like growth factors (IGFs) did not change the growth effects elicited by RA. The addition of IGFBP-3 (1,000 ng/mL) inhibited the growth of Hep 3B cells and counteracted the growth-stimulatory activity of RA, but not completely, suggesting that RA has direct growth-stimulatory activity and that this is enhanced by autocrine down-regulation of IGFBP-3. IGFBP-3 also inhibited the growth of PLC/PRF/5 cells and of Hep G2 cells. Treatment with phosphorylated IGFBP-1 (1,000 ng/mL) alone or with RA did not affect the growth of PLC/PRF/5 cells or Hep G2 cells. However, addition of dephosphorylated IGFBP-1, derived from in vivo dephosphorylation of the phosphorylated form, stimulated the growth of both cell lines, independent of interaction with IGF-I. From these observations, we propose that RA down-regulates IGFBPs, which in turn causes autocrine modulation of cell growth independent of IGF in hepatoma cells in vitro or in vivo. In addition, RA regulates IGFBPs at the posttranscriptional (Hep 3B cells and Hep G2 cells) or transcriptional level (PLC/PRF/5 cells) in a cell-specific manner.

Carcinoma, Hepatocellular↗
PubMed1999

Effect of delivery on anal sphincter morphology and function.

PURPOSE: Anal sphincter injury is a serious complication of childbirth, which may result in persistent anal incontinence. Occult injuries, visualized with endoanal ultrasonography, have previously been reported in up to 35 percent of females in a British study. The aim of the present study was to study anal sphincter morphology and function before and after delivery in primiparous females in the United States. METHODS: Thirty-eight primiparous patients (mean age, 31 years) were evaluated with endoanal ultrasonography, anal manometry, and pudendal nerve terminal motor latency during pregnancy and after delivery. Bowel function before and after delivery was recorded according to set questionnaires. Cesarean section was performed in three patients. RESULTS: Clinical sphincter tears, requiring primary repair, occurred in 15 percent of the patients. After delivery endoanal ultrasonography revealed disruptions in the external anal sphincter in six patients, but no patient had disruption in the internal anal sphincter. One patient had slight scarring in the external sphincter. Of the seven patients with pathologic findings at endoanal ultrasonography, the left pudendal latency increased after delivery (P < 0.05), and manometric results were reduced. Three of these seven patients had a third-degree or fourth-degree tear during delivery. All investigations were normal in the three patients who underwent cesarean section. CONCLUSIONS: The present study demonstrates a significant frequency of sphincter injuries (20 percent) after vaginal delivery. Obstetricians should be aware of this risk and explicitly inquire about incontinence symptoms at follow-up after delivery.

Adult↗
PubMed1999

Two cases of common bile duct stone after liver transplantation.

Biliary complications after orthotopic liver transplants are a continuing cause of morbidity and mortality. Biliary stones and sludge are less well known complications of hepatic transplantation, although they have long been recognized. Recently we experienced two cases of biliary stones developed after liver transplantation. One 32-year-old male, who frequently admitted due to recurrent cholangitis, was treated with percutaneous transhepatic biliary drainage and choledochojejunostomy with cholecystectomy. The other 58-year-old male, who had stones in commone bile duct, was treated by endoscopic manipulation. They are in good condition without recurrent bile duct stones or its accompanying complications. Although stones and sludge are relatively infrequent after liver transplantation, surgical or interventional radiologic treatments are usually performed for treatment.

Adult↗
PubMed1999

Effects of exposure conditions to footshocks early in life on spontaneous locomotor activity at maturity in rats.

Both genetic and environmental factors are involved in establishing a behavior. An animal study was done to determine the characteristics of interaction between genetic (nature) and environmental (nurture) factors. Delivery of footshocks (0.8 mA x 60 times, at random) early in life was used as the environmental stimulus. As the footshock was delivered repeatedly, a rat showed helplessness behavior and the number of shocks necessary to elicit helplessness was measured to quantify the trait of an animal in coping with the aversive environmental stimulus. The nocturnal ambulatory activity at adulthood was measured as a behavioral expression of the nature-nurture interaction. Although the experience of footshocks early in life did not significantly alter average activity levels at adulthood, the activity was positively correlated with the number of shocks necessary to elicit helplessness (nature) while receiving footshocks (nurture) on postnatal day 14. Additionally, a second exposure to identical shock parameters on postnatal day 21 reversed the relationship. These results clearly showed that an interaction between nature and nurture during infancy leads to substantial behavioral alterations later in life, and suggest that the nature-dependent determination of an adult behavior can be modified in different directions by the conditions of an environmental experience early in life.

Aging↗
PubMed1999

Surface treatments of titanium in aqueous solutions containing calcium and phosphate ions.

Immersion treatment of titanium in aqueous solutions containing various kinds of ion concentrations of calcium and phosphate (pH 5.8, 7.0, and 8.0) were attempted to accelerate calcium phosphate precipitation on titanium in body fluid. The performance was confirmed using scanning electron microscopy, X-ray diffractometry, and Fourier transformed infrared absorption spectrometry with a reflection absorption spectrometer of the specimen immersed in Hanks' solution. Calcium phosphate precipitation on titanium in Hanks' solution is accelerated by the immersion treatment in aqueous solutions containing calcium and phosphate ions. The amount, composition, and shape of calcium phosphate precipitate vary according to the pH and ion concentrations of the solutions in which titanium is immersed. This method is effective for the surface treatment of inside pore narrow space of titanium materials.

Biocompatible Materials↗
PubMed1998

Phylogenetic analysis of the nef gene reveals a distinctive monophyletic clade in Korean HIV-1 cases.

To study the genetic variation of the HIV-1 strains prevalent in South Korea, we analyzed the nef sequences derived from 46 HIV-1-positive individuals living in various geographic regions in Korea. Phylogenetic analysis revealed four subtypes of HIV-1: A (3 patients), B (41 patients), D (1 patient), and a type that could not be clearly classified to any known subtype (1 patient). Thirty-five of the 41 Korean subtype B isolates formed a distinct monophyletic clade that is not related to any of the international sequences from the Los Alamos Database or GenBank as of June 1997. Indeed, the presence of unique conserved sequences was identified among the Korean isolates in this Korean subtype B group. The variations in the nucleotide sequences of a majority (32 of 35) subtype B samples within the Korean clade were 1.9% to 8.8%, and amino acid sequences varied from 3.9% to 15.5%. These results suggest that HIV-1 strains currently present in South Korea might have originated from a few sources or might be developing through a certain selective pressure. This is the first report on the molecular nature of the HIV-1 infection present in South Korea.

Adolescent↗
PubMed1998

Transanal treatment of rectal cancer: ablative methods and open resection.

Conservative surgical techniques are an alternative to radical surgery for selected patients with rectal carcinoma. The goals of conservative management are to select patients with low risk for nodal metastases and achieve local tumor control while preserving anal sphincter function. Patient selection is critical to achieve this outcome because properly selected patients can obtain results comparable to radical surgery. Selection is based on preoperative histologic characteristics and endorectal ultrasonography. Predictors of pelvic lymph node metastasis risk include tumor grade, depth of penetration, mucinous features, and vascular and lymphatic invasion. Endorectal ultrasound (ERUS) is important in accurately staging the lesion by identifying both depth of invasion and presumptive nodal status. The options for local therapy reviewed include techniques of full-thickness local excision and ablative procedures including endocavitary irradiation, electrocoagulation, and laser therapy. The techniques of full-thickness transanal excision and endocavitary irradiation are described with results from the University of Minnesota experience.

Anal Canal↗
PubMed1998

Perineal body measurement improves evaluation of anterior sphincter lesions during endoanal ultrasonography.

UNLABELLED: Endoanal ultrasonography has become an important tool in the evaluation of patients with anal incontinence. However, the extent of anterior defects is sometimes difficult to quantitate during endoanal ultrasonography. PURPOSE: This study was designed to evaluate perineal body measurement during endoanal ultrasonography in assessing patients with obstetric anal sphincter injuries. METHODS: Forty-two patients with anal incontinence because of obstetric sphincter injuries and 13 asymptomatic subjects were investigated with endoanal ultrasonography. Sphincter muscle thickness, sphincter defects, and perineal body were measured. Perineal body measurement was performed by inserting a finger, held gently against the posterior vaginal wall, into the vagina and measuring the distance between the inner surface of the internal sphincter and the ultrasonographic reflection of the finger. RESULTS: All patients had anterior sphincter lesions of varying extent. Mean size of internal sphincter lesions was 146 degrees, and mean size of external sphincter lesions was 107 degrees (P < 0.001). Perineal body measurement was performed without difficulty in all patients and subjects. Perineal body measurement (mean +/- standard deviation) was 6 +/- 2 mm in patients and 12 +/- 3 mm in asymptomatic subjects (P < 0.001). Ninety-three percent of patients had perineal body measurement < or = 10 mm, and 70 percent of asymptomatic subjects had perineal body measurement > 10 mm. Digital delineation of the perineal body during endoanal ultrasonography improved the visualization of sphincter lesions in 74 percent of patients. CONCLUSIONS: Digital delineation of the perineal body during endoanal ultrasonography improved the visualization of sphincter lesions in the majority of patients. Perineal body measurement is performed without difficulty and is a good predictor of anterior sphincter lesions. Use of this technique improves visualization of sphincter lesions.

Adult↗
PubMed1998

The development of a new method to detect the adulteration of commercial aloe gel powders.

Simple and accurate methods to detect the adulteration of commercial aloe gel powder were developed. Crude polysaccharide in aloe gel powder was isolated by precipitating with excess ethyl alcohol and total hexose in isolated polysaccharide was determined by Dubois assay. After hydrolysis of non-dialysable polysaccharides, resultant free sugar was determined by gas chromatography for sugar recognition and ash contents was considered simultaneously. In some products, the content of ash was very low while the content of total hexose was very high. And polysaccharides of these products revealed typical dextran pattern, therefore, these products could be identified that adulterated with commercial maltodextrin. The content of maltodextrin in adulterated product was determined by HPLC and TLC analysis which could be adopted as a part of a certification process.

Aloe↗
PubMed1998

Whole-body [18F]FDG PET in the management of metastatic brain tumours.

BACKGROUND: To determine its roles in the diagnosis and the systemic evaluation of metastatic brain tumours, whole-body positron emission tomography (PET) using [18F]FDG was performed in 20 consecutive patients. METHODS: All patients were thought to be suffering or needing to be differentiated from metastatic brain tumours. Nine patients had multiple brain lesions; six were older and showed a rim-enhancing lesion with surrounding oedema; seven had homogeneously enhancing periventricular lesion(s) on computed tomography (CT) and/or magnetic resonance (MR) imaging, thought to be central nervous system lymphomas. Two patients had skull mass(es) and two patients had a solid mass suspected to be, respectively, a haemorrhagic metastasis and a metastatic malignant melanoma. All of them received whole-body [18F]FDG PET and conventional systemic work-up for metastasis in order to compare the results of the two methods. RESULTS: Metastatic brain tumours were diagnosed on whole-body [18F]FDG PET in eleven patients who had extracranial and intracranial hypermetabolic lesions. In nine of these, a conventional work-up also detected primary lesions which on whole-body [18F]FDG PET were seen to be hypermetabolic foci. Systemic lymph node metastases were detected by whole-body [18F]FDG PET only in two patients and histological diagnosis was possible by biopsy of lymph nodes rather than of brain lesions. In the remaining nine patients who had only intracranial hypermetabolic foci, histological diagnosis was made by craniotomy or stereotactic biopsy. It was confirmed that seven of nine patients were suffering from a primary brain tumour and two from metastatic carcinoma. None of the nine showed evidence of systemic cancer on conventional work-up. Histological diagnoses of the primary brain tumours were four cases of primary central nervous system lymphoma and one each of multifocal glioblastoma, Ewing's sarcoma, and cavernous angioma. Patients felt no discomfort during the whole-body [18F]FDG PET procedure and there were no complications. The false negative rate in [18F]FDG PET and in conventional work-up was 15.4% and 30.7% respectively. There were no false positives on either [18F]FDG PET or conventional work-up. CONCLUSION: It is suggested that whole-body [18F]FDG PET is a safe, reliable, and convenient method for the diagnosis and systemic evaluation of patients thought to be suffering or needing to be differentiated from a metastatic brain tumour.

Adult↗
PubMed1998

Gliomatosis cerebri: clinical features, treatment, and prognosis.

To clarify clinical features and to elucidate prognostic factors and prognosis, the authors retrospectively analyzed 16 cases of gliomatosis cerebri treated at Seoul National University Hospital between January 1988 and December 1995. Age at diagnosis ranged from 19 to 62 (median 34) years and male to female ratio was 10:6. Most presented with headache or seizure, and the mean duration of symptoms was 12.8 months. A poorly defined diffuse high signal intensity lesion, extending in T2-weighted images for two lobes or more, was the characteristic magnetic resonance (MR) image finding. On postcontrast T1-weighted MR imaging, focal enhancement of the lesion was detected in five cases. All patients underwent histological confirmation by craniotomy (9 cases) or stereotactic biopsy (7 cases). Histologically, all patients had compatible findings of gliomatosis cerebri which are the widespread infiltration of neoplastic glial cells with minimal destruction of pre-existing structures. After histological diagnosis, external radiation therapy was begun except in one case, who declined this treatment. Fourteen patients completed the whole procedure and received the planned dose (mean 5780 cGy). Median survival time after diagnosis was 38.4 months. In univariate analysis, the Ki-67 labelling index (> 1) showed significant correlation with the length of survival (p = 0.006). It is suggested that 1) gliomatosis cerebri can be diagnosed by a combination of MR imaging findings and histological examination; 2) histological diagnosis and external radiation therapy might be a good treatment modality; 3) the Ki-67 labelling index correlates significantly with survival time.

Adult↗
PubMed1998

Lincomycin abrogates dexamethasone-enhanced melanogenesis in B16 melanoma cells.

The effects of lincosamide, and interference between the effects of glucocorticoid and lincosamide, on melanogenesis were determined in B16 melanoma cells. Cells were treated for 4 days with lincomycin (LM) and/or dexamethasone (DX) at equimolar concentrations ranging from 10(-9) M to 10(-5) M, or at various concentrations of DX with 10(-6) M LM. Effects on proliferation, tyrosinase activity, melanin biosynthesis, and levels of mRNA for tyrosinase, tyrosinase-related protein 1 (TRP1), and tyrosinase-related protein 2 (TRP2) were examined. Treatment with LM or LM + DX stimulated proliferation of melanoma cells with minimal cytotoxicity, while DX did not influence cell proliferation either alone or in combination with LM. Treatment with LM alone increased tyrosinase activity slightly and reduced melanin content in a dose-dependent manner. However, LM counteracted the pronounced increase in tyrosinase elicited by DX and also abrogated the dose-dependent increase in melanin content elicited by DX. Treatment with LM alone did not affect mRNA levels for tyrosinase, TRP1, or TRP2. Furthermore, LM abrogated the DX-induced up-regulation of mRNAs for tyrosinase and the down-regulation of TRP1 mRNA. These results suggest that LM inhibits melanogenesis post-transcriptionally and abrogates glucocorticoid-induced melanogenesis at the transcriptional level in B16 melanoma cells.

Animals↗
PubMed1998

Acute cholecystitis: comparison of MR cholangiography and US.

PURPOSE: To evaluate the clinical usefulness of magnetic resonance (MR) cholangiography in the assessment of acute cholecystitis by comparing the diagnostic accuracy of MR cholangiography with that of ultrasonography (US). MATERIALS AND METHODS: Thirty-five patients with symptoms of acute cholecystitis underwent both US and MR cholangiography before cholecystectomy, which helped confirm acute cholecystitis. Two reviewers evaluated US and MR cholangiographic images for evidence of calculi and gallbladder wall thickening and compared these findings with surgical findings. RESULTS: MR cholangiography depicted all 21 (100%) calculi and one false-positive calculus in the cystic duct and gallbladder neck, but US depicted only one (14%) of seven cystic duct calculi and 12 (86%) of 14 gallbladder neck calculi. In the diagnosis of cystic duct obstruction, MR cholangiography had a sensitivity of 100%, a specificity of 93%, and an accuracy of 97%. US had a sensitivity of 62%, a specificity of 100%, and an accuracy of 77%. In the diagnosis of gallbladder wall thickening, MR cholangiography had a sensitivity of 69%, a specificity of 83%, and an accuracy of 71%. US had a sensitivity of 96%, a specificity of 83%, and an accuracy of 94%. CONCLUSION: In the assessment of acute cholecystitis, US is superior to MR cholangiography in the evaluation of gallbladder wall thickening. However, MR cholangiography is superior to US in the depiction of cystic duct and gallbladder neck calculi at the evaluation of cystic duct obstruction.

Acute Disease↗
PubMed1998

Large glial cyst of the pineal gland: a possible growth mechanism. Case report.

The authors report on a patient who presented with a large symptomatic glial cyst of the pineal gland communicating with the third ventricle. The hole between the ventricle and the cyst, suspected on magnetic resonance images, was found at surgery. The to-and-fro flow mechanism is considered to be involved in the pathogenesis of growth in this unusual large glial cyst of the pineal gland, although this mechanism cannot be applied universally.

Adult↗
PubMed1998

Experience of orthotopic liver transplantation in 11 patients with liver cirrhosis from Korea: medical factors affecting outcome.

Orthotopic liver transplantation (OLT) has evolved to become a standard treatment of choice for end-stage liver diseases. The present study was performed to evaluate the peri-operative medical factors affecting transplantation outcome and to determine if patients with type B viral cirrhosis were acceptable for OLT. A total of 11 patients with end-stage cirrhosis, who have received OLT in Kangnam St. Mary's Hospital since May 1993, included 8 HBV-related cases, 1 Hepatitis C Virus (HCV)-related case, and 2 non-B, non-C cases. One-year cumulative survival rate by Kaplan-Meier method was 43.7%. Factors significantly associated with 1-year survival of the recipients during pre-OLT period were performance status and modified Pugh-Child score (p=0.015 and p=0.015, respectively). Among those 4 patients who lived longer than 1 year, 3 of 4 patients with HBsAg-positive had no HBV re-infection with our protocol. These results suggest that, to improve the outcome of OLT in cirrhosis patients, transplantation should be performed in the stage when patients maintain better performance and hepatic functional reserve during the end-stage of liver cirrhosis. In addition, patients with cirrhosis caused by HBV infection may be indicated for OLT, because HBV re-infection is preventable effectively with a high-dose hepatitis B immunoglobulin protocol.

Adolescent↗