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Y H Kim

Publications and source records attributed to Y H Kim.

At least 163 records · Page 9Linked to original sources
PubMed2001

Strain distribution in the proximal human femur. An in vitro comparison in the intact femur and after insertion of reference and experimental femoral stems.

Six pairs of human cadaver femora were divided equally into two groups one of which received a non-cemented reference implant and the other a very short non-dependent experimental implant. Thirteen strain-gauge rosettes were attached to the external surface of each specimen and, during application of combined axial and torsional loads to the femoral head, the strains in both groups were measured. After the insertion of a non-cemented femoral component, the normal pattern of a progressive proximal-to-distal increase in strains was similar to that in the intact femur and the strain was maximum near the tip of the prosthesis. On the medial and lateral aspects of the proximal femur, the strains were greatly reduced after implantation of both types of implant. The pattern and magnitude of the strains, however, were closer to those in the intact femur after insertion of the experimental stem than in the reference stem. On the anterior and posterior aspects of the femur, implantation of both types of stem led to increased principal strains E1, E2 and E3. This was most pronounced for the experimental stem. Our findings suggest that the experimental stem, which has a more anatomical proximal fit without having a distal stem and cortex contact, can provide immediate postoperative stability. Pure proximal loading by the experimental stem in the metaphysis, reduction of excessive bending stiffness of the stem by tapering and the absence of contact between the stem and the distal cortex may reduce stress shielding, bone resorption and thigh pain.

Adult↗
PubMed2001

A comparison of polyethylene wear in hips with cobalt-chrome or zirconia heads. A prospective, randomised study.

We have reviewed 70 patients with bilateral simultaneous total hip arthroplasties to determine the rate of failure and to compare polyethylene wear and osteolysis between an implant with a cobalt-chrome head and Hylamer liner with that of a zirconia head and Hylamer liner. The mean thickness of the polyethylene liner was 11.0 mm (8.8 to 12.2) in the hip with a zirconia head and 10.7 mm (8.8 to 12.2) in that with a cobalt-chrome head. At follow-up at 6.4 years no acetabular or femoral component had been revised for aseptic loosening and no acetabular or femoral component was loose according to radiological criteria in both the cemented and cementless groups. The mean rate of linear wear and annual wear rate were highest in the 22 mm zirconia femoral head (1.25 mm (SD 1.05) and 0.21 mm (SD 0.18), respectively) and lowest in the 22 mm cobalt-chrome femoral head (0.70 mm (SD 0.39) and 0.12 mm (SD 0.07), respectively). The mean volumetric wear was highest in the 28 mm zirconia femoral head (730.79 mm ) and lowest in the 22 mm cobalt-chrome femoral head (264.67 mm3), but if the results were compared by size of the femoral head and type of material there was no statistical difference (p > 0.05). Sequential measurements of annual wear showed that the zirconia femoral head had a relatively higher rate of penetration than the cobalt-chrome head over the first three years; thereafter the rate of wear was reduced and compared favourably with that of cobalt-chrome heads. There was a statistically significant relationship between the wear of the polyethylene liner and the age of the patient, male gender and the degree of abduction angle of the cup, but not diagnosis, weight, hip score, range of movement, or amount of anteversion. Osteolysis was identified on both sides of the acetabulum in six patients (9%). Of 12 hips with acetabular osteolysis, six had a 28 mm cobalt-chrome femoral head and the remaining six a 28 mm zirconia head. Osteolysis was observed in zones 1A and 7A of the femur in two hips (3%) with a 28 mm zirconia head (cemented hip) and in four (6%) with a 28 mm cobalt-chrome femoral head (cementless hip). Our findings suggest that although the performance of a zirconia femoral head with a Hylamer liner was not statistically different from that of a cobalt-chrome femoral head and Hylamer liner, there was a trend for the zirconia head to be worse than the cobalt-chrome femoral head.

Adult↗
PubMed2001

Collection efficiency of metallic contaminants on si wafer by vapor-phase decomposition-droplet collection.

The collection efficiency of metallic contaminants on four different types of silicon wafers was investigated. P, p+, n and n(+)-type polished silicon wafers were used for the substrate, and 14 metallic elements (Na, Mg, Al, K, Ca, Cr, Fe, Mn, Co, Ni, Cu, Zn, Mo and Ti) were contaminated on silicon wafer surface. Vapor-phase decomposition-droplet collection (VPD-DC) was employed as the sample preparation procedure. For the collecting solution, HNO3, HF and a mixture of HF and H2O2 were used, respectively. A liquid droplet collecting metallic contaminants during VPD-DC was analyzed by inductively coupled plasma-mass spectrometry (ICP-MS). As a result, it was found that HNO3 and HF were not suitable for collecting Cu. Copper was not collected completely in HNO3 and HF. A mixture of HF and H2O2 is the most effective to collect all of the tested metallic elements, regardless of the dopant concentration and type of substrate.

Journal Article↗
PubMed2001

Idiopathic multilocular thymic cyst: CT features with clinical and histopathologic correlation.

OBJECTIVE: We performed this study to describe the CT features of idiopathic multilocular thymic cysts with clinical and histopathologic correlation. CONCLUSION: Multilocular thymic cysts typically manifest on CT as unilocular or multilocular cystic thymic masses, often with soft-tissue attenuation components. CT cannot be used to distinguish neoplastic from nonneoplastic soft-tissue components.

Adolescent↗
PubMed2001

Serum factors associated with neovascular glaucoma following vitrectomy for proliferative diabetic retinopathy.

We performed a retrospective study of serum factors associated with neovascular glaucoma that can occur following vitrectomy for proliferative diabetic retinopathy. The medical records of 183 patients (241 eyes) who received vitrectomy between August 1996 and August 2000 were studied retrospectively and subsequently analyzed by linear logistic regression analysis and multiple logistic regression tests. Neovascular glaucoma developed at an average of 2.7 months in 31 of 241 eyes (14.1%). The overall anatomical success rate of retinal attachment was 82.5% (199 eyes in 241 eyes), although it decreased to 45.1% (14 eyes in 31 eyes) in eyes with neovascular glaucoma. Serum cholesterol (P = 0.041) and fibrinogen levels (P = 0.020) were significantly associated with the development of neovascular glaucoma. However, no significant association could be found concerning hypertension, diabetic retinopathy or hypercholesterolemia (P > 0.05). We suggest that serum creatinine, cholesterol and fibrinogen levels can be used to predict the development of neovascular glaucoma in vitrectomized eyes with diabetic retinopathy and can further provide a more active approach to preventing the development of this condition.

Adult↗
PubMed2001

Altered remodeling of nucleolar machineries in cultured hepatocytes treated with thioacetamide.

Thioacetamide (TA) is converted into a hyperacetylating agent which causes hepatic necrosis, regeneration, cirrhosis and cancerous transformation. One of the most characteristic toxicities of TA in rat is observed with a 50 mg/kg per day which induces nucleolar enlargement different from that in regenerating liver. From TA-treated liver, the nucleoli were isolated and characterized for an altered nucleolar signal transduction system. Immunochemistry revealed that the poisoned nucleoli had increased levels of both nucleolus specific proteins (nucleophosmin and nucleolin) and various signal molecules (CK2, Erk1/2, p38, protein kinases A and C, and cyclin A). Using flow cytometry, the nucleoli were found to be in G2-arrested nuclei. Manifestation of the nucleolar enlargement could be readily observed using an ex vivo hepatocyte culture. There were two types of nucleolar enlargement. One was observed in normal hepatocytes with light density of enlarged nucleoli. The other was in TA-treated hepatocytes with dense and compact density of enlarged nucleoli, which contained a 3 to 5-fold higher nudeophosmin content than the control. In vitro induction of nucleolar enlargement with TA was possible. As soon as the hepatocytes anchored on a collagen coat, exogeneous TA (higher than 1 microg/mL) could induce dense and compact nucleoli. However, when an exogeneous drug was added after monolayer formation (1 day), no drug-induced nucleolar enlargement was observed.

Animals↗
PubMed2001

Clinical characteristics of constrictive pericarditis diagnosed by echo-Doppler technique in Korea.

A retrospective analysis of clinical data of 71 patients with constrictive pericarditis (CP) diagnosed by echo-Doppler technique (mean age, 49+/-17) was done. In 27 patients (38%), the etiology was unknown, and the three most frequent identifiable causes were tuberculosis (23/71, 32%), cardiac surgery (8/71, 11%), and mediastinal irradiation (6/71, 9%). Pericardiectomy was performed in 35 patients (49%) with a surgical mortality of 6% (2/35), and 11 patients (15%, 11/ 71) showed complete resolution of constrictive physiology with medical treatment. Patients with transient CP were characterized by absence of pericardial calcification, shorter symptom duration, and higher incidence of fever, weight loss, and tuberculosis. The 5-yr survival rates of patients with transient CP and those undergoing pericardiectomy were 100% and 85+/-6%, respectively, which were significantly higher than that of patients without undergoing pericardiectomy (33+/-17%, p=0.0083). Mediastinal irradiation, higher functional class, low voltage in ECG, low serum albumin, and old age were the independent variables associated with a higher mortality. Tuberculosis is still the most important etiology of CP in Korea, and not infrequently, it may cause transient CP. Early diagnosis and decision-making using follow-up echocardiography are crucial to improve the prognosis of patients with CP.

Adult↗
PubMed2001

Choroidal tuberculoma with membranous glomerulonephritis.

We report treatment of a 24-year-old man with membranous glomerulonephritis (MGN) who developed a solitary choroidal tuberculoma in association with miliary tuberculosis during steroid therapy. In June 1995, the patient had developed nephrotic syndrome. He had refused renal biopsy at that time. So we treated him with corticosteroids having assumed a diagnosis of minimal change nephrotic syndrome. After initial corticosteroids and diuretics therapy for 5 months, his generalized edema resolved but proteinuria (3 positive) continued, suggesting the presence of other forms of glomerulonephritis. Renal biopsy performed in January 1996. The patient was diagnosed as having MGN. The patient was closely observed over a period of 34 months and remained stable without steroid therapy. However at 34 months, generalized edema was again noted and steroid therapy at high dosage was initiated. After 5 months of steroid therapy, he developed miliary tuberculosis and a solitary choroidal mass. An antituberculosis chemotherapeutic regimen was started and after a further 5 months, all clinical symptoms and signs of the pulmonary lesion were resolved and a measurable shrinking of the choroidal mass was recorded.

Adult↗
PubMed2001

Restoration of atrial mechanical function after successful radio-frequency catheter ablation of atrial flutter.

BACKGROUND: Atrial mechanical dysfunction and its recovery time course after successful radiofrequency ablation of chronic atrial flutter (AFL) has been largely unknown. We serially evaluated left atrial function by echocardiography after successful ablation of chronic atrial flutter. METHODS: In 13 patients with chronic AFL, mitral E wave A wave, and the ratio of A/E velocity were measured at 1 day, 1 month, 3 months and 6-12 months after successful radiofrequency (RF) ablation. Doppler tissue imaging (DTI) technique was also used to avoid load-dependent variation in the flow velocity pattern. RESULTS: Left atrial mechanical function, assessed by A wave velocity and the annular motion, was depressed at 1 day, but improved significantly at 1 month and maintained through 6-12 months after the ablation. Left atrial size did not change significantly. CONCLUSION: Left atrial mechanical function was depressed immediately after successful RF ablation of chronic AFL, but it improved significantly after 1 month and was maintained over one year.

Adult↗
PubMed2001

Fra-1 expression in malignant and benign thyroid tumor.

BACKGROUND: The differential diagnosis of thyroid nodules is very important in deciding the treatment modality and the fine needle aspiration is the best diagnostic method. But, there are some limitations in use because of inadequate test materials and difficulty in interpreting. According to the study of oncogene and tumor suppressor gene about the origin of thyroid tumor, expression of Fra-1, one of AP-1 complex, is increased in thyroid neoplasm, though not present in the normal tissue. So, there is a possibility that it will be used as a method for the differential diagnosis of thyroid nodules. We tried to know whether presence or absence of Fra-1 expression can be used as a diagnostic method in differential diagnosis of thyroid nodules using the immunohistochemical (IHC) staining method. METHODS: In 4 types of thyroid tumor that were confirmed by histologic diagnosis after operation (18 cases of adenomatous goiter, 16 cases of follicular adenoma, 30 cases of papillary cancer, 10 cases of follicular cancer), IHC staining method was performed to evaluate the expression of Fra-1. RESULTS: In papillary and follicular thyroid cancers, the expression of Fra-1 was stronger than in benign thyroid tumor, but there was no difference in Fra-1 expression between the two types of carcinoma. Weak expression of Fra-1 was observed in all cases of follicular adenoma, though it was weaker than in carcinoma, and it was also weakly expressed only in some cases (33%) of adenomatous goiter. CONCLUSION: The expression of Fra-1 was stronger in thyroid cancer than in benign thyroid tumor, but it was impossible to differentiate thyroid cancer from benign thyroid tumor by presence or absence of Fra-1 expression using IHC staining method.

Biomarkers, Tumor↗
PubMed2001

Perception of wheezing in the elderly asthmatics.

BACKGROUND: In elderly asthmatics, underdiagnosis is one of the important features. The main reason for underdiagnosis is thought to be a low frequency in complaining of symptoms due to the reduction of intellectual recognition and physical activity. Among the various symptoms, wheezing is the principal clue in diagnosing bronchial asthma, and decreased complaints for wheezing are also noted in elderly asthmatics. The objective of this study is to determine if less complaints of wheezing in elderly asthmatic is due to decrease in the development of wheezing. METHODS: 61 young (20-39 years old), 68 middle-aged (40-59 years old) and 65 elderly (older than 60 years old) stable asthmatic subjects were studied (each group shall be called, hereafter, Young Group, Middle-aged Group and Old Group, respectively). During the methacholine induced airway narrowing, lung auscultation and questionnaire survey about presence and perception of wheezing were conducted in 194 asthmatics. RESULTS: One hundred and sixty-nine patients (87%) developed wheezing during the methacholine induced airway obstruction. The frequency of wheezing during the methacholine challenge was found to be comparable among the groups. The methacholine concentration, % fall in FEV1, and FEV1 levels of the initial detection of wheezing were not different among the groups. Among the patients who developed wheezing, 47 patients (77%), 42 patients (61.8%) and 26 patients (40%) complained of wheezing in Young, Middle and Old Group, respectively. CONCLUSION: In conclusion, the decreased perception of wheezing is a main factor for the low frequency of complaints of wheezing in elderly asthmatics.

Adult↗
PubMed2001

A case of mediastinal angiomyolipoma.

Angiomyolipoma is a common tumor of the kidney but has rarely been found in the mediastinum. We report a case of angiomyolipoma of the posterior mediastinum in a 62-year-old woman. She experienced exertional dyspnea and intermittent cough at admission. Computed tomography indicated a tumor located at the left paravertebral and upper posterior mediastinum and MRI imaging demonstrated a mass with low signal intensity in T1-weighted image at T4-5 level. Thoracotomy was done for surgical removal of the tumor and histologic examination revealed a mesenchymal tumor composed of mature fat, capillaries and smooth muscle fibers. The tumor was immunohistochemically positive for CD34 and factor-VIII (for vascular component) smooth muscle actin (for smooth muscle component) and S-100 protein (for fat component). There have been four case reports about mediastinal angiomyolipoma, namely three Japanese cases and one French case. It is suggested that angiomyolipoma could be considered for the differential diagnosis of mediastinal tumors.

Angiomyolipoma↗
PubMed2001

Ultrasonographic evaluation of the gallbladder: comparison of fundamental, tissue harmonic, and pulse inversion harmonic imaging.

The purpose of our study was to compare pulse inversion harmonic imaging, tissue harmonic imaging, and fundamental imaging in the evaluation of normal and diseased gallbladder. Gallbladders in 170 patients were examined with fundamental imaging, tissue harmonic imaging, and pulse inversion harmonic imaging using a 2- to 5-MHz curved array transducer. Images were divided into normal and abnormal groups. The sharpness of the wall and degree of internal artifact were evaluated in normal groups, and lesion conspicuity and internal artifact were evaluated in abnormal groups. In images of both normal and abnormal gallbladder, significant differences were demonstrated among the 3 imaging methods (P < .001), and pulse inversion harmonic imaging provided the best image quality and the least artifact. Tissue harmonic imaging was the next best, providing better image quality and less artifact than fundamental imaging. In conclusion, pulse inversion harmonic imaging provided the best image quality and the least artifact among the 3 ultrasonographic methods in the evaluation of both normal and abnormal gallbladder.

Aged↗
PubMed2001

Anti-inflammatory effect of the aqueous extract from Lonicera japonica flower is related to inhibition of NF-kappaB activation through reducing I-kappaBalpha degradation in rat liver.

We investigated the anti-inflammatory effects of aqueous extract from Lonicera japonica flower (AELJ), a traditional skin rash drug, in lipopolysaccharide (LPS)-induced rat liver sepsis. Immunoblot analysis showed that the level of nuclear factor (NF)-kappaBp65 was rapidly up-regulated and inhibitory (I)-kappaBalpha was down-regulated by LPS challenge. However, AELJ inhibited the increase of NF-kappaBp65 and degradation of I-kappaBalpha in the liver of LPS-challenged rats. Immunohistochemical analysis of rat hepatocytes showed that LPS-induced inflammatory responses, involving degradation of I-kappaBalpha and induction of NF-kappaBp65, tumor necrosis factor (TNF)-alpha and inducible nitric oxide synthase (iNOS), are partially inhibited by pretreatment with AELJ. These results suggest that AELJ may act as a therapeutic agent for inflammatory disease through a selective regulation of NF-kappaB activation.

Animals↗
PubMed2001

Expression of the apolipoprotein C-II gene during myelomonocytic differentiation of human leukemic cells.

Apolipoprotein C-II (apoC-II), which is known to activate lipoprotein lipase (LPL), was identified by ordered differential display (ODD)-polymerase chain reaction (PCR) as a cDNA fragment exhibiting a distinct increase in expression during 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced differentiation of promonocytic U937 cells into monocytes and macrophages. The amount of apoC-II mRNA expression detectable in U937 cells significantly increased and reached a maximum 24-48 h after treatment with 32 nM TPA. apoC-II mRNA was also detected in monocytic THP-1 cells but was not detected in promyelocytic HL-60 cells. In healthy human tissues, the most significant expression of apoC-II mRNA was in the liver. Although apoC-II mRNA expression was markedly up-regulated during the induced differentiation of HL-60 cells into monocytes and macrophages with 32 nM TPA, such expression was not induced during the differentiation of HL-60 cells into granulocytes with 1.25% dimethyl sulfoxide. These results suggest that human apoC-II expression is induced at the transcription level during myelomonocytic differentiation and may confer an important role to macrophages involved in normal lipid metabolism and atherosclerosis.

3T3 Cells↗
PubMed2001

Glottic closing force in an anesthetized, awake pig model: biomechanical effects on the laryngeal closure reflex resulting from altered central facilitation.

Reflex sphincteric closure of the larynx, essential to lower airway protection, is most efficiently achieved through strong reflex adduction by both vocal cords. Because the conversion of a bilaterally evoked response to a unilaterally evoked one appears anesthesia-dependent, we hypothesized that central facilitation is an essential component of a bilateral adductor reflex and that its disturbance could result in weakened sphincteric closure. Six adult 50 kg pigs were used in this study. During electrical stimulation of the internal branch of the superior laryngeal nerve (iSLN) using bipolar platinum-iridium electrodes, the force of the evoked glottic closure response was measured using a pressure transducer positioned between both vocal cords, while electromyographic evoked response was recorded from both thyroarytenoid muscles under varying levels [0.5-1.0 minimal alveolar concentration (MAC)] of isoflurane anesthesia. The force of glottic closure appeared less under deep anesthesia, even with bilateral stimulation of the iSLN, than under light anesthesia with unilateral stimulation. As anesthetic levels approached 1.0 MAC, the glottic closing force decreased to 52-72% of the force measured under 0.5 MAC light anesthesia. Although it is generally understood that alteration of central facilitation by deepening anesthesia abolishes the crossed adductor reflex, the biomechanical effects of altered central facilitation on force differentials have never been previously demonstrated. Precise understanding of this effect may improve the prevention of aspiration in patients emerging from heavy sedation or under prolonged psychotropic control.

Anesthesia↗
PubMed2001

Detection of canine distemper virus (CDV) through one step RT-PCR combined with nested PCR.

A one step reverse transcription PCR (RT-PCR) combined nested PCR was set up to increase efficiency in the diagnosis of canine distemper virus (CDV) infection after developement of nested PCR. Two PCR primer sets were designed based on the sequence of nucleocapsid gene of CDV Onderstepoort strain. One-step RT-PCR with the outer primer pair was revealed to detect 10(2) PFU/ml. The sensitivity was increased hundredfold using the one-step RT-PCR combined with the nested PCR. Specificity of the PCR was also confirmed using other related canine virus and peripheral blood mononuclear cells (PBMC) and body secretes of healthy dogs. Of the 51 blood samples from dogs clinically suspected of CD, 45 samples were revealed as positive by one-step RT-PCR combined with nested PCR. However, only 15 samples were identified as positive with a single one step RT-PCR. Therefore approximately 60% increase in the efficiency of the diagnosis was observed by the combined method. These results suggested that one step RT-PCR combined with nested PCR could be a sensitive, specific, and practical method for diagnosis of CDV infection.

Animals↗