• Proceedings of the PSK Conference
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• 2003.10b
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• pp.99.3-100
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• 2003

It is desirable to improve the tumor targeting and blood clearance pharmacokinetics of radiolabeled monoclonal antibodies. To achieve this goal, several avidin-biotin (Bt) binding systems have been developed to decouple large molecular weight antibodies from small radiolabels, thereby achieving high tumor-to-background radioactivity ratios. We inserted a readily catabolizable linker, triglycine (TG), between 3-［/sup125/I］iodobenzoate and dendrimer (G3). We also neutralized the positive charges of G3 by acylation with tetrafluorophenyl glycolate, thereby blocking proximal tubular reabsorption of G3 mediated by charge attraction. (omitted)

• The Korean Journal of Nuclear Medicine
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• v.28 no.2
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• pp.220-226
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• 1994

This study was performed to evaluate the clinical applicability of the reverse transcription polymerase chain reaction (RT-PCR ) kit of HCV-RNA using biotinylated and radioiodinated primers. Study subjects were 118 patients with positive anti-HCV. HCV-RNA in patient's serum was extracted by guanidium thiocyanate method. After first amplification, the product was reamplified by primers labelled with biotin and I-125. The final amplification product was defected by counting the radioactivity after incubation in avidin coated tubes. In 51 samples, the test was repeated for evaluation of reproducibility. This new method was also compared with conventional RT-PCR methods in 34 samples from patients with chronic liver disease. The results were as follows ; 1) HCV-RNA was positive in 85(97%)of 88 patients with chronic liver disease, and in 23 (73%) of 30 patients with normal liver function. 2) In comparison with conventional method, HCV-RNA was detected in 32(94%) of 34 patients with new method, whereas in 27(79%) of the same group with conventional method. 3) Repeated test with new method in 52 samples demonstrated 82% of concordant result. In conclusion, new method with biotinylated and radioiodinated primers was more sensitive than conventional method. However, great care must be taken for quality control because there were considerable interassay variation and possiblity of false positivity and false negativity.

• Tuberculosis and Respiratory Diseases
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• v.62 no.1
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• pp.43-50
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• 2007

Background: Mutated or deregulated expression of C-erbB-2 causes this gene to function as a potent oncogene. Vascular endothelial growth factor (VEGF) is a crucial angiogenic molecule in lung cancer. Both C-erbB-2 and VEGF can promote growth, proliferation and metastasis in non-small cell lung cancer (NSCLC). The purpose of this study was to investigate evaluate the relationship between the expressions of the C-erbB-2 and VEGF genes using immunohistochemistry. Materials and Methods: Ninety-five patients with NSCLC were involved (60 squamous cell carcinoma and 35 adenocarcinoma). The formalin-fixed paraffin embedded specimens were immunohistochemically stained for C-erbB-2 and VEGF using the avidin-biotin complex method. Results: Positive C-erbB-2 expression was observed more often in adenocarcinomas than squamous cell carcinomas (p<0.05). Although the immunohistochemical expressions of C-erbB-2 and VEGF in non-small-cell lung cancer showed increased tendencies at an advanced stage, the correlation between early and advanced cancers was insignificant. In adenocarcinomas, the expressions of VEGF and C-erbB-2 were significantly (p<0.05). Conclusion: The overexpression fo C-erbB-2 was significantly higher in adenocarcinomas than squamous cell carcinomas, and correlated with the expression of VEGF in adenocarcinomas of the lungs.

• Parasites, Hosts and Diseases
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• v.29 no.4
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• pp.397-402
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• 1991

Paragonimus westermani is a common fluke in Korea. The present study aimed to determine serum total IgE and specific IgG levels in experimental paragonimiasis of rats. Each Wistar rat was inoculated orally with 20~25 metacercariae of P. westermani from Cambaroides similis. Before and after infection(1,2,3,4,6,8 weeks) of P. westermani, the blood was collected from the retro- orbital venous plexus of rats and kept serum at $-70^{\circ}C$. Serum total IgE and specific IgG levels were determined by the capture and conventional enzyme-linked immunosorbent assay, respectively. The results were as follows; 1. Serum IgE values were increased to 0. 18${\pm}$0.042 at 2 weeks, $0.28{\pm}0.151$ at 4 weeks and 0.43${\pm}0.055$ at 8 weeks after infection. The absorbances of non-infected rats ranged $0.07{\pm}0.021~0.12{\pm}0.025$. 2. Specific IgG values were slightly increased at 3 weeks ($0.20{\pm}$0.032) and gradually increased up to 8 weeks($0.31{\pm}0.067$) after infection. The absorbances of non-infected rats ranged $0.11{\pm}0.035~0.18{\pm}0.019$. The present results suggested that p. westermani could elevate serum IgE and specific IgG antibodies in Wistar rats which were not a good definitive host.

• Korean Journal of Veterinary Research
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• v.37 no.2
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• pp.235-244
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• 1997

The present study was performed to investigate the patterns of appearance of lectin in trachea of fetuses of 60, 90 and 120 days old and neonates of Korean native goat. Carbohydrate markers were used in histochemistry for the determination of the lectin by staining of avidin-biotin-peroxidase complex(ABC), and the markers consisted of biotin-labeled concanavalin A(Con A), dolichos biflorus agglutinin(DBA), rincinus communis agglutinin(RCA-I), ulexeuropalus communis agglutinin(UEA) and wheat germ agglutinin(WGA). 1. The Con A-binding reactions appeared moderately on the apical surface of the tracheal epithelia in 60 days old fetuses, and the reactions were similar on the tracheal epithelia and glands in 90 and 120 days old fetuses and neonates. 2. Reaction of the DBA appeared as the strongest meanwhile the DBA-binding reactions were determined strongly on the apical surface of the tracheal epithelia in the 60 days old fetuses. Reaction for the DBA on the tracheal epithelia and glands of 90 and 120 days old fetuses and neonates were in same manner. 3. The RCA-I-binding reactions appeared very strongly on the apical surface of the tracheal epithelia in 60 and 90 days old fetuses. Reaction to the RCA-1 appeared moderately on certain apical surface of tracheal epithelia and glands in 120 days old fetuses and neonates. 4. No reactions provoked for the UEA in trachea of 60 days old fetuses and neonates, but the UEA-binding reactions appeared moderately in the tracheal epithelia of 90 days old fetuses and weakly in 120 days old fetuses. 5. The WGA-binding reactions appeared very strongly on the apical surface of the tracheal epithelia in 60 and 90 days old fetuses, and moreover, the reactions were determined on the luminal surface of the tracheal gland in 90 days old fetuses. On the other hand, goblet cells of the tracheal epithelia and glands in neonates reacted moderately to the WGA.

• The Korean Journal of Pain
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• v.9 no.2
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• pp.326-335
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• 1996

Background: Though a number of studies have described the distribution of substance P(SP)-like immunoreactivity in the spinal cord, they have been focused on lamina I and II of the dorsal horn and there are little morphological studies on the topographic distribution and ultrastructure of the SP immunoreactive neurons especially in the ventral horn of the spinal cord. this study was conducted to identify distribution pattern of SP immunoreactive neurons and to difine the synaptic organization of their processes in ventral horn of the thoracic cord of the cat by preembbeding immunocytochemical method using SP antiserum. Methods: Five adults cats of either sex were used and deeply anesthetized by intramuscular injection of ketamine. After removal of the spinal cord, samples of thoracic cord were taken and placed in fresh fixative at $4^{\circ}C$ for 2 hours. Transverse sections $50{\mu}m$ thick were processed using the preembbeding immunocytochemical method and incubated consecutively in the specific primary antibody and the 10% normal goat serum, the rabbit anti-substance P antiserum, the biotin-labelled goat anti-rabbit IgG and finally the avidin-biotin-peroxidase complex. The processed tissue sections were throughly washed and stained in the black with 1% uranyl acetate. Section were examined on a electron microscope. Results: 1) SP immunoreactive neurons were observed in the gray matter around central canal. 2) In lamina I and II SP immunoreactivity was observed in both myelinated and unmyelinated nerve fibers, but in ventral horn only in the unmyelinated nerve fibers. 3) SP immunoreactive axon terminals with small round and large dense core vesicles made chemical synapses onto the dendrites of motor neurons in the ventral horn. Conclusion: SP immunoreactive neurons might play an important role in modulation of motor neurons in the ventral horn of the thoracic cord of the cat.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.337-342
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• 2007

Conventional methods for pathogen detection and identification are labor-intensive and take days to complete. Biosensors have shown great potential for the rapid detection of foodborne pathogens. Fiber-optic biosensors have been used to rapidly detect pathogens because they can be very sensitive and are simple to operate. However, many fiber-optic biosensors rely on manual sensor handling and the sandwich assay, which require more effort and are less sensitive. To increase the simplicity of operation and detection sensitivity, a binding inhibition assay method for detecting Listeria monocytogenes in food samples was developed using an automated, fiber-optic-based immunosensor: RAPTOR (Research International, Monroe, WA, USA). For the assay, fiber-optic biosensors were developed by the immobilization of Listeria antibodies on polystyrene fiber waveguides through a biotin-avidin reaction. Developed fiber-optic biosensors were incorporated into the RAPTOR to evaluate the detection of L. monocytogenes in frankfurter samples. The binding inhibition method combined with RAPTOR was sensitive enough to detect L. monocytogenes ($5.4{\times}10^7\;CFU/mL$) in a frankfurter sample.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1154-1158
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• 2004

The classical ABC (avidin-biotin peroxidase complex) method for immunohistochemistry in the paraffin-embedded tissues bring into being disadvantage such as low sensitivity of antigen detection and highly background. The biotinyl-tyramide conjugation recently introduced for sensitive immunohistochemistry was applied to light microscopy in paraffin-embedded pancreatic and liver tissues. The protocol consists of an indirect method in which 4-5㎛ tissue sections are reacted successively within a specific primary antibody, followed by a biotinylated secondary antibody, streptavidin-horseradich peroxidase (HRP), and then finally with biotinyl-tyramide. The labeling obtained for insulin and collagen antigen tested in pancreatic and liver tissues, respectively, was found to be highly specific with the labeling for each antigen confined to its particular cellular compartment. In this study, fish (flounder) serum was specially applied to remove nonspecific binding. Background levels and nospecific deposition of the staining were negligible. This results suggest that super-signal induction method by biotinyl-tyramide conjugate can readily applied to antigen detection of the paraffin-embedded tissues.

• Korean Journal of Veterinary Research
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• v.32 no.2
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• pp.227-233
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• 1992

Out of twenty rabbits which died of rabbit hemorrhagic disease spontaneously occurring in Korea, five animals had a concurrent infection with Encephalitozoon cuniculi in the cerebrum. The lesions were composed of granulomas, leptomeningitis and perivascular cuffing with mononuclear cells. The granulomas consisted of a central necrotic focus surrounded by an infiltration with plasma cells, lymphocytes and macrophages. Gliosis was associated with the granulomas. Gram-positive organisms were detected in the cerebrum from two rabbits. They were oval to rod-shaped with blunt round ends. The distribution of the pathogens was investigated by the direct avidin-biotin peroxidase complex method. They were present in pseudocysts and macrophages. Pseudocysts were found in the granulomas as well as the neuropil without cellular reactions. Some organisms were present within reticulo-endothelial cells of blood capillaries and macrophages in the subarachnoid spaces. These organisms had ultrastructural characteristics consistent with Encephalitozoon cuniculi.

• Journal of Biosystems Engineering
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• v.34 no.4
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• pp.254-259
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• 2009

Conventional methods for pathogen detection and identification are labor-intensive and take several days to complete. Recently developed biosensors have shown potential for the rapid detection of foodborne pathogens. In this study, an impedimetric biosensor was developed for rapid detection of Salmonella typhimurium. To develop the biosensor, an interdigitated microelectrode (IME) was fabricated by using semiconductor fabrication process. Anti-Salmonella antibodies were immobilized based on either avidin-biotin binding or self assembled monolayer (SAM) on the surface of the IME to form an active sensing layer. To evaluate effect of antibody immobilization methods on sensitivity of the sensor, detection limit of the biosensor was analyzed with Salmonella samples innoculated in phosphate buffered saline (PBS) or food extract. The impedimetric biosensor based on SAM immobilization method produced better detection limit. The biosensor could detect 107 CFU/mL of Salmonella in pork meat extract. This method may provide a simple, rapid, and sensitive method to detect foodborne pathogens.