Preliminary Evaluation of the URiSCAN SUPER and Usefulness of a New Urine Reagent Strip to Detect Ascorbic Acid / 임상검사와정도관리

BACKGROUND: Ascorbic acid can cause false negative results in the detection of urinary hemoglobin (Hb) with reagent test strips. The fully automated urine analyzer URiSCAN SUPER (YD Diagnostics, Korea), which can measure ascorbic acid, was recently developed. We compared the URiSCAN SUPER to the semi-automated urine analyzer URiSCAN PRO II (YD Diagnostics) and evaluated the usefulness of a new reagent strip to detect ascorbic acid. METHODS: A total of 641 urine samples were used to evaluate the agreement between the two analyzers. In addition we performed urine microscopic examinations to investigate the sensitivity and specificity of urinary Hb and white blood cells. We determined the detection limit of urine ascorbic acid. We also determined the positive rate of ascorbic acid and the false negative rate for urinary Hb. Additionally, the interference effect of ascorbic acid for urinary Hb was investigated. RESULTS: The agreement rate between the two analyzers was greater than 98% for all tests except for urinary specific gravity. The detection limit of urine ascorbic acid was 10 mg/dL. The positive rate of ascorbic acid was 49.8%. The false-negative rate for urinary Hb was 6.0% and 2.8% (P>0.05) in the presence and absence of urine ascorbic acid, respectively. CONCLUSIONS: The performances of the two urine analyzers were comparable. URiSCAN SUPER for the detection of urinary Hb was resistant to interference by ascorbic acid. Since the URiSCAN SUPER performs a fully automated analysis, it would be useful in urine screening.

In Vitro Effects of Threapeutic Low Energy Ultrasound on Cultured Humon Articular Chondrocyte / 대한정형외과학회잡지

Ultrasound has been applied therapeutically to accelerate connective tissue healing and healing of long bone fracture. We performed this study to evaluate the effect of therapeutic low energy ultrasound on cultured human articular chondrocyte. Chondrocytes were isolated from articular cartilage of knee joint of young adult during notchy plasty of ACL reconstructive procedure using collagenase and cultured in DMEM solution. Therapeutic ultrasounds ( Intensity ; 1W/cm2, 0.75W/cm2, 0.25W/cm2. Frequency ; 1 MHz) were applied at the cultured human articular cartilage for 0, 30, 60, 90 seconds, repectively. 3H-Thymidine uptake, 3H-Uridine uptake and production of collagen Type I, Type II were evaluated on 3 days, and 5 days of culture. Decreased cell proliferation, decreased thymidine and uridine uptake, decreased production of human collagen Type I and complete loss of production of human collagen Type II were showed after high dose ultrasound application( 1W/cm2, 0.75W/cm2, 1MHz). After low dose ultrasound application( 0.25W/cm2, 1MHz), there were increased cell proliferation and increased production of human collagen Type II and production of Type I collagen was not changed after 3 days and 5 days. In summary, this study showed that decreased cell proliferation and collagen synthesis were observed with application of high dose ultrasound, whereas, increased cell proliferation and human collagen Type II synthesis were observed with application of low dose ultrasound.

Joint Symptoms in Henoch - Schonlein Purpura / 대한정형외과학회잡지

Henoch-Sch nlein purpura is a small-vessel vasculitis characterized by palpable purpura, abdominal pain, hematuria and arthralgia. Joint involvement occurs in 2/3 of the cases and the joint symptoms are misapprehended as an orthopaedic problem because they are often severe and occurs before characteristic purpura. It has been reported that the joint symptoms can be improved without any sequelae. But, recently some authors suggest that severe joint destruction can occur when combined with rheumatoid arthritis and the patients are FILA-DR4 positive. So, the regular follow-up for joint symptoms and screening test for the risky patients having possibility for progression of arthritis are required. In order to increase the attention of the orthopaedic surgeons on this disease and study the progression of joint symptoms, possibility of development of screening test for the risky patients and the characterisitics of the disease, we analyzed the 58 patients of Henoch-Sch nlein purpura. The following results were obtained. Among 58 patients 34 cases were male and 25 cases were female, 5 to 10-year-old children were affected more frequently and the disease occurs frequently in spring and winter season. Joint symptoms developed in 22/58 patients(37.9%) and occurs before characteristic purpura in 5/22 patients(22.7%) among the joint symptom-developed patients. Knee and ankle were affected in most patients and the inflammatory signs such as high fever, leukocytosis and elevated ESR were accompanied with joint symptom, so it resembled the symptoms and signs of pyogenic arthritis. Most of the patients recovered without remaining sequelae but 9 patients(15.5%) among joint symptom-developed patients complained repeated attacks of arthralgia. The HLA B27 were all positive in those patients. So, it was assumed that the joint symptom in Henoch-Sch nlein purpura has a correlation with genetic environment and through the broad prospective study, the HLA typing can be a screening test for the risky group prone to suffer from repeated attack or aggravation of arthritis.

Affinity of Osteoblasts on Bone Cements Incorporated with Amino Groups / 대한정형외과학회잡지

Biomaterial surfaces can be characterized by their chemical, morphologic, and electrical surface features. The adhesion and proliferation of different types of mammarian cells on various surfaces depends on polymer surface characteristics like water wettability and charge. In clinical aspect, bone to bone cement interface loosening has been one of the causes of failure of the prosthetic implantation. In this study, the bone cement was, thus, modified by mixing a monomer with amino group, which is a positively charged chemical group, to improve cellular adhesion and proliferation and to decrease bone to bone cement interface loosening. To incorporate amino-charged groups in the bone cement, we used dimethylaminoethyl- metacrylate (DAEMA) as a adding material. As experimental materials, CMW1 bone cement (control) and CMW1 mixed with monomer containing 1mol% dimethylaminoethylmetacrylate (DMA1) and CMW1 mixed with monomer containing 3mo1% dimethylaminoethylmetacrylate (DMA3) were used. To estimate the wettability of surface of bone cement, water contact angle was measured using contact angle goniometer and water absorption was measured using the disc samples. Osteoblasts were isolated from neonatal, Spraque-Dawley rat calvaria. After 3 culturing passages, the osteoblasts were plated on the cement disks, which are placed in a 24-well tissue-culture plate, at a density of 1 X 10 (5) cells/cm. After culturing for 2, 6, 24, and 48 hours, the number of attached cells on each cement discs were counted and cell morphologies were examined with scanning electron microscope (SEM). No significant difference in the water contact angle (63-64degrees) is statistically found between 3 groups (P>0.05). The water absorbencies of DMA1 (3.61+/-0.28%) and DMA3 (6.70+/-0.56%) were higher than that of the control (2.59+/-0.21%). Diametral tensile strength were decreased at DMA1 and DMA3 groups in comparing with control and that of DMA3 was smallest (P0.05) at each culturing period. In summary, well spread osteoblasts and increased attachment and growth of them were observed, when they were plated on the amino-charged cement discs. The histocompatibility of the amino-charged cements may increase the attachment between bone and cement. However, mechanical strength may decrease due to higher water absorbency. The author will further study to find the material that is cytocompatible and that does not lead to deteriorate mechanical properties.