• Applied Chemistry for Engineering
• /
• v.33 no.2
• /
• pp.173-178
• /
• 2022

A lateral flow immunoassay (LFIA) method using carbon nanodot@silica as a signaling material was developed for analyzing the concentration of retinol-binding protein 4 (RBP4), one of the lung cancer biomarkers. Instead of antibodies mainly used as bioreceptors in nitrocellulose membranes in LFIA for protein detection, aptamers that are more economical, easy to store for a long time, and have strong affinities toward specific target proteins were used. A 5' terminal of biotin-modified aptamer specific to RBP4 was first reacted with neutravidin followed by spraying the mixture on the membrane in order to immobilize the aptamer in a porous membrane by the strong binding affinity between biotin and neutravidin. Carbon nanodot@silica nanoparticles with blue fluorescent signal covalently conjugated to the RBP4 antibody, and RBP4 were injected in a lateral flow manner on to the surface bound aptamer to form a sandwich complex. Surfactant concentrations, ionic strength, and additional blocking reagents were added to the running buffer solution to optimize the fluorescent signal off from the sandwich complex which was correlated to the concentration of RBP4. A 10 mM Tris (pH 7.4) running buffer containing 150 mM NaCl and 0.05% Tween-20 with 0.6 M ethanolamine as a blocking agent showed the optimum assay condition for carbon nanodot@silica-based LFIA. The results indicate that an aptamer, more economical and easier to store for a long time can be used as an alternative immobilizing probe for antibody in a LFIA device which can be used as a point-of-care diagnosis kit for lung cancer diseases.

• Journal of Life Science
• /
• v.33 no.4
• /
• pp.305-314
• /
• 2023

Ultraviolet B (UVB) irradiation causes skin diseases by inducing cellular oxidative stress, photoaging, and inflammation. This study aimed to investigate the protective effects of morin against UVB-induced oxidative stress in normal human dermal fibroblasts (NHDFs). Morin has been reported to be a potential therapeutic candidate for oxidative stress-mediated diseases, neurodegenerative diseases, and inflammation. Since morin has been identified as a potential antioxidant, we speculated that morin could alleviate UVB-induced apoptosis in NHDFs. Cell viability and intracellular reactive oxygen species (ROS) levels were measured using the MTT assay, H2DCFDA, and the DHE staining method, respectively. Lipid peroxidation and protein carbonyl formation were tested using ELISA kits. DNA fragmentation and comet assay were used to assess DNA damage. Apoptotic bodies were analyzed using Hoechst 33342 staining and TUNEL assay. The expression of apoptosis-related proteins was examined using Western blot analysis. Morin showed a cyto-protective effect by scavenging UVB-induced ROS, increasing the expression of antioxidant-related proteins and inhibiting UVB-induced oxidative alterations such as lipid peroxidation, protein carbonylation, and DNA damage. Morin protects against UVB-induced cell apoptosis by inhibiting Bcl-2-associated X protein, caspase-9, and caspase-3 expression, while increasing the expression of the anti-apoptotic protein Bcl-2. These effects of morin were conferred through decreased phosphorylation of p38 and c-Jun N-terminal kinase 1/2. The results demonstrated that morin may be developed as a preventive/therapeutic drug to be used to prevent UVB-induced skin damage.

• Laboratory Medicine Online
• /
• v.1 no.2
• /
• pp.100-104
• /
• 2011

Background: Malaria is a problematic disease in Korea, and microscopic examination of Giemsa-stained blood smear has been used as the gold standard for its diagnosis. However, this technique is time-consuming and has low sensitivity in samples with low numbers of malarial parasites (<20 parasites/μL). Here, we evaluated the performance characteristics of the LG Advansure^TM Malaria P.f./P.v. real-time QPCR (LG life sciences, Korea). Methods: Blood samples from 173 persons who visited Korea University Ansan Hospital were evaluated. QPCR was performed in 73 malaria patients and 100 healthy subjects by using the LG Advansure Malaria P.f./P.v. real-time QPCR^R kit, and the results were compared with those of microscopy. The detection limit of this kit was determined by serial dilution of Plasmodium-infected blood with normal blood (blood not infected with Plasmodium). Results: Among the 73 patients that were microscopically confirmed to have malaria (Plasmodium vivax infection, N=70, P. falciparum infection, N=3), 69 patients were diagnosed with P. vivax infection and 3 were diagnosed with P. falciparum infection by LG Advansure^TM Malaria P.f./P.v. realtime QPCR. Both the tests indicated absence of infection in the 100 healthy subjects. The detection limit of LG Advansure^TM Malaria P.f./P.v. real-time QPCR was 0.1 parasite/μL. Conclusions: LG Advansure^TM Malaria P.f./P.v. real-time QPCRis a very sensitive and specific technique and can be used as a confirmatory test for malaria.

• Childhood Kidney Diseases
• /
• v.9 no.2
• /
• pp.175-182
• /
• 2005

Purpose : Interleukin 1 receptor antagonist(IL-1ra) is an endogenous antiinflammatory agent that binds to IL-1 receptor and thus competitively inhibits the binding of IL-1$\alpha$ and IL-1$\beta$. Allele 2 in association with various autoimmune diseases has been reported. In order to evaluate the influence of IL-1ra gene VNTR polymorphism on the susceptibility to HSP and its possible association with disease severity, manifested by severe renal involvement and renal sequelae, we studied the incidence of carriage rate and allele frequency of the 2 repeats of IL-1ra allele 2($IL1RN^{*}2$) of the IL-1ra gene in children with HSP with and without renal involvement. Methods : The IL-1ra gene polymorphisms were determined in children with HSP with(n=40) or without nephritis(n=34) who had been diagnosed at Busan Paik Hospital and the control groups(n=163). Gene polymorphism was identified by PCR amplification of the genomic DNA. Results : The allelic frequency and carriage rate of $IL1RN^{*}1$ were found most frequently in patients with HSP and in controls. The allelic frequency of $IL1RN^{*}2$ was higher in patients with HSP compared to that of controls($4.7\%\;vs.\;2.5\%$, P=0.794). The carriage rate of $IL1RN^{*}2$ was higher In patients with HSP compared to that of controls($8.1\%\;vs.\;6.8\%$, P=0.916). The allelic frequency of $IL1RN^{*}2$ was higher in patients with HSP nephritis compared to that of HSP($5.3\%\;vs.\;2.9\%$, P=0.356). The carriage rate of $IL1RN^{*}2$ was higher in Patients with HSP nephritis compared to that of HSP($10.0\%\;vs.\;5.9\%$, P=0.523). Among 13 patients with heavy proteinuria(>1.0 g), 11 had $IL1RN^{*}1$, 1 had $IL1RN^{*}2$ and the others had $IL1RN^{*}4$. At the time of last follow up 4 patients had sustained proteinuria and their genotype was $IL1RN^{*}1$. Conclusion : The allelic frequency and carriage rate of $IL1RN^{*}1$ were found most frequently in patients with HSP and in controls. Our study suggests that the carriage rate and allele frequency of the 2-repeats of IL-1lra allele 2($IL1RN^{*}2$) of the IL-1ra gene may not be associated with susceptibility and severity of renal involvement in children with HSP (J Korean Soc Pediatr Nephrol 2005;9:175-182)

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.8 no.1
• /
• pp.12-20
• /
• 2005

Purpose: Helicobacter pylori infection is known to be associated with acute or chronic abdominal pain and upper gastrointestinal bleeding in children. This study was performed to analyze the gastroduodenoscopic findings and the efficacy of triple therapy with omeprazole, amoxicillin and clarithromycin between one and two weeks of duration in children with H. pylori infection. Methods: We have assessed retrospectively 60 patients presented with acute or chronic abdominal pain or upper gastrointestinal bleeding. H. pylori infection was confirmed by endoscopic biopsy and rapid urease test. Out of 60 patients, 30 patients were treated with a combination of omeprazole, amoxicillin, and clarithromycin for one week, and the other 30 patients were treated for two weeks with the same medication. Efficacy of treatment was assessed 4 weeks after the termination of treatment by using the $^{13}C$ urea breath test. Results: The 60 patients with the complaint of diffuse abdominal pain, epigastric pain, vomiting or hematemesis were included in this study. One-week treatment group (group I) consisted of 30 patients (14 male, 16 female) with mean age of $11.6{\pm}2.67years$. Two-week treatment group (group II) consisted of 30 patients (11 male, 19 female) with mean age of $10.7{\pm}4.17years$. In group I, H pylori were eradicated in 26 out of 30 patients (86.7%). In group II, H. pylori were eradicated in 26 out of 30 children (86.7%). Both groups did $^{13}C$ urea breath test after 4 weeks after termination of the triple therapy. The eradication rates were same in both groups as 86.7%, 26 out of 30 patients in each group. The results of endoscopy were nodular gastritis 26 (43.3%), erosive gastritis 10 (16.7%), hemorrhagic gastritis 7 (11.7%), gastric ulcer 2 (3.3%) and normal finding 15 (25.0%). Conclusion: In this study, the nodular gastritis was most common endoscopic findings with H. pylori positive patients. The eradication rate of H. pylori with omeprazole, amoxicillin and clarithromycin was 86.7% and it would be highly effective as primary treatment with no significant differences in the eradication rate between one-week and two-week treatment groups. However, we should need more long-term follow-up data.