• Journal of Life Science
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• v.20 no.6
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• pp.907-913
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• 2010

Human enteroviruses (HEV) are considered one of the major infectious causes of central nervous system infections such as aseptic encephalomeningitis in pediatrics. This study was focused on providing information related to genetic characteristics and diversities of HEV which prevailed between 2007 and 2009 in Busan, Korea. A total of 2,743 specimens were collected from children and screened for isolation of HEV by cell culture and RT-PCR. Among the specimins, 240 isolates were grouped into 21 different HEV serotypes using VP1 RT-PCR. The major etiological agents were CV-A6 and CV-B2 in 2007, E-6 and E-30 in 2008 and CV-B1 in 2009. The occurrence of HEV infections was the most frequent in the summer (May to August, 188 cases, 78.3%). Most of the isolates were identified from specimens from children under 10 years old, with the highest occurrence in the 2 to 4 year old range (15.2%). However, there were no significant differences between male and female children for the isolates. For analyzing genetic characterization, VP1 gene was amplified by RT-PCR and sequenced. The phylogenetic tree was established by Clustal W method using DNASTAR software. Using the sequence analysis of the VP1 region, it was classified into 2 groups; HEV-A and HEV-B. The HEV-A group contained 6 serotypes and sequences of 31 isolates were compared within each serotype. The HEV-B group contained 10 serotypes and the sequences of 41 isolates were compared within each serotype. Homology analysis of the VP1 region showed that the identity scores of HEV-A and B isolates were different. In conclusion, genetic divergences were observed among the isolates from children between 2007 and 2009 in Busan.

• Journal of Life Science
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• v.33 no.1
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• pp.56-63
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• 2023

In this study, two cases of food poisoning caused by Salmonella that occurred in Gyeongsangnam-do in September 2021 are reported. One of the outbreaks occurred in a school and the other in a company. The molecular epidemiological characteristics of the isolated strains in the two outbreaks were analyzed. In the case of the school outbreak, 29 (4.9%) of 588 individuals experienced diarrhea and abdominal pain. As a result of a test of 36 individuals (patients, n=29; cook workers, n=7), Salmonella enterica serotype Enteritidis was detected in 17 (47.2%) patients, suggesting this serotype was the principal cause. Meanwhile, Salmonella spp. were not detected in 35 food and environmental samples. In the company outbreak, 87 (3.0%) of 2,900 individuals who had intaked from the same source experienced diarrhea, abdominal pain, and fever. In a test of 50 individuals (patients, n=40; cook workers, n=10), S. Enteritidis was detected in 28 patients (56.0%). Also, Vibrio cholerae (NAG) was detected in four patients with S. Enteritidis, and V. cholerae (NAG) only was detected in one patient. Salmonella spp. were not detected in 118 preserved foods, but S. Enteritidis was detected in one eaten food (toast) delivered in group by the company. Through PFGE genetic homology analysis of the isolated strains, all S. Enteritidis detected in patients and consumed foods were the same type. It seems that these S. Enteritidis isolates were the same type as detected in a previous school outbreak and in patients of group food poisoning in other regions, leading to an enhanced problem of food poisoning and epidemiology. Our analytic results can provide data for epidemiological management and food poisoning prevention based on molecular characteristics.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.12
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• pp.4773-4780
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• 2014

Background: To investigate the effects of small interference RNA (siRNA) targeting BCR/ABL mRNA on proliferation and apoptosis in the K562 human chronic myeloid leukemia (CML) cell line and to provide a theoretical rationale and experimental evidence for its potential clinical application for anti-CML treatment. Materials and Methods: The gene sequence for BCR/ABL mRNA was found from the GeneBank. The target gene site on the BCR/ABL mRNA were selected according to Max-Planck-Institute (MPI) and rational siRNA design rules, the secondary structure of the candidate targeted mRNA was predicted, the relevant thermodynamic parameters were analyzed, and the targeted gene sequences were compared with BLAST to eliminate any sequences with significant homology. Inhibition of proliferation was evaluated by MTT assay and colony-formation inhibiting test. Apoptosis was determined by flow cytometry (FCM) and the morphology of apoptotic cells was identified by Giemsa-Wright staining. Western blotting was used to analyze the expression of BCR/ABL fusion protein in K562 cells after siRNA treatment. Results: The mRNA local secondary structure calculated by RNA structure software, and the optimal design of specific siRNA were contributed by bioinformatics rules. Five sequences of BCR/ABL siRNAs were designed and synthesized in vitro. Three sequences, siRNA1384, siRNA1276 and siRNA1786, which showed the most effective inhibition of K562 cell growth, were identified among the five candidate siRNAs, with a cell proliferative inhibitory rate nearly 50% after exposure to 12.5nmol/L~50nmol/L siRNA1384 for 24,48 and 72 hours. The 50% inhibitory concentrations ($IC_{50}$) of siRNA1384, siRNA1276 and siRNA1786 for 24hours were 46.6 nmol/L, 59.3 nmol/L and 62.6 nmol/L, respectively, and 65.668 nmol/L, 76.6 nmol/L, 74.4 nmol/L for 72 hours. The colony-formation inhibiting test also indicated that, compared with control, cell growth of siRNA treated group was inhibited. FCM results showed that the rate of cell apoptosis increased 24 hours after transfecting siRNA. The results of annexinV/PI staining indicated that the rate of apoptosis imcreased (1.53%, 15.3%, 64.5%, 57.5% and 21.5%) following treamtne with siRNAs (siRNA34, siRNA372, siRNA1384, siRNA1276 and siRNA1786). Morphological analysis showed td typical morphologic changes of apoptosis such as shrunken, fragmentation nucleus as well as "apoptotic bodies" after K562 cell exposure to siRNA. Western blot analysis showed that BCR/ABL protein was reduced sharply after a single dose of 50nmol/L siRNA transfection. Conclusions: Proliferation of K562 cells was remarkbly inhibited by siRNAs (siRNA1384, siRNA1276 and siRNA1786) in a concentration-dependent manner in vitro, with effective induction of apoptosis at a concentration of 50 nmol/L. One anti-leukemia mechanism in K562 cells appeared that BCR/ABL targeted protein was highly down-regulated. The siRNAs (siRNA1384, siRNA1276 and siRNA1786) may prove valuable in the treatment of CML.

• Microbiology and Biotechnology Letters
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• v.37 no.3
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• pp.248-257
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• 2009

The inhibitors against Vibrio harveyi quorum sensing (QS) signaling were developed by modifying the molecular structure of the major signal, N-3-hydroxybutanoyl-L-homoserine lactone (3-OH-$C_4$-HSL). A series of structural derivatives, N-(3-hydroxysulfonyl)-L-homoserine lactones (HSHLs) were synthesized by the solid-phase organic synthesis method. The in vivo QS inhibition by these compounds was measured by a bioassay system using the V. harveyi bioluminescence, and all showed significant inhibitory effects. To analyze the interaction between these compounds and LuxN, a 3-OH-$C_4$-HSL receptor protein of V. harveyi, we tentatively determined the putative signal binding domain of LuxN based on the sequence homology with other acyl-HSL binding proteins, and predicted the partial 3-D structure of the putative signal binding domain of LuxN by using ORCHESTRA program, and further estimated the binding poses and energies (docking scores) of 3-OH-$C_4$-HSL and HSHLs within the domain. In comparison of the result from this modeling study with that of in vivo bioassay, we suggest that the in silica interpretation of the interaction between ligands and their receptor proteins can be a valuable way to develop better competitive inhibitors, especially in the case that the structural information of the protein is limited.