• Title/Summary/Keyword: Cross infection control

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Analysis of whole genome sequencing and virulence factors of Vibrio vulnificus 1908-10 isolated from sea water at Gadeok island coast

  • Hee-kyung Oh;Nameun Kim;Do-Hyung Kim;Hye-Young Shin;Eun-Woo Lee;Sung-Hwan Eom;Young-Mog Kim
    • Fisheries and Aquatic Sciences
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    • v.26 no.9
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    • pp.558-568
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    • 2023
  • Vibrio vulnificus is an aquatic bacterium causing septicemia and wound infection in humans. To understand this pathogen at the genomic level, it was performed whole genome sequencing of a cefoxitin-resistant strain, V. vulnificus 1908-10 possessing virulence-related genes (vvhA, viuB, and vcgC) isolated from Gadeok island coastal seawater in South Korea. The genome of V. vulnificus 1908-10 consisted of two circular contigs and no plasmid. The total genome size was estimated to be 5,018,425 bp with a guanine-cytosine (GC) content of 46.9%. We found 119 tRNA and 34 rRNA genes respectively in the genome, along with 4,352 predicted protein sequences. Virulence factor (VF) analysis further revealed that V. vulnificus 1908-10 possess various virulence genes in classes of adherence, antiphagocytosis, chemotaxis and motility, iron uptake, quorum sensing, secretion system, and toxin. In the comparison of the presence/absence of virulence genes, V. vulnificus 1908-10 had fur, hlyU, luxS, ompU, pilA, pilF, rtxA, rtxC, and vvhA. Of the 30 V. vulnificus comparative strains, 80% of the C-genotype strains have all of these genes, whereas 40% of the E-genotype strains have all of them. In particular, pilA were identified in 80% of the C-type strains and 40% of the E-type strains, showing more difference than other genes. Therefore, V. vulnificus 1908-10 had similar VF characteristics to those of type C strains. Multifunctional-autoprocessing repeats-in-toxin (MARTX) toxin of V. vulnificus 1908-10 contained 8 A-type repeats (GXXGXXXXXG), 25 B.1-type repeats (TXVGXGXX), 18 B2-type repeats (GGXGXDXXX), and 7 C-type repeats (GGXGXDXXX). The National Center for Biotechnology Information (NCBI) Basic Local Alignment Search Tool (BLAST) showed that the RtxA protein of V. vulnificus 1908-10 had the effector domain in the order of cross-liking domain (ACD)-C58_PaToxP-like domain- α/β hydrolase-C58_PaToxP-like domain.

Analysis of Critical Control Points through Field Assessment of Sanitation Management Practices in Foodservice Establishments (현장실사를 통한 급식유헝별 위생관리실태 분석)

  • Kwak Tong-Kyung;Lee Kyung-Mi;Chang Hye-Ja;Kang Yong-Jae;Hong Wan-Soo;Moon Hye-Kyung
    • Korean journal of food and cookery science
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    • v.21 no.3 s.87
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    • pp.290-300
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    • 2005
  • Increased sanitation management of foodservice establishments is required because most of the reported foodborne-disease outbreaks were in the foodservice industry. The purpose of this study was to determine the important control points for good sanitation. In this study, we inspected twenty foodservice establishments in Seoul, Kyunggi, Kyungnam with a self-developed monitoring tool. These foodservice establishments included secondary schools, universities, and industries. Six of them had appointed as the HACCP-certified establishments from the Korea Food and Drug Administration. The inspection was conducted from June to August in 2002. The inspection tool consisted of nine dimensions and sixty-five items. The dimensions were 'personal sanitation', 'supply of raw food', 'food storage', 'handling of raw food and ready-to-eat', 'cleaning and sterilization', 'waste control', 'pest control', and 'control of establishment and equipment' The highest possible score of this inspection tool is 105 points. Statistical data analysis was completed using the SPSS Package(11.0) for descriptive analysis Kruskal-Wallis. The score for the secondary schools (83.6 points) was higher than for the others and number of in compliance item was 50.9 on average. Therefore, we concluded that the secondary schools' sanitation condition was good. The foodservice establishments acquired HACCP certification was 89.7 points, which was significantly higher than that of establishments not applying foodservices in total score. Instituting the HACCP system in a foodservice is very effective for sanitation management. Many out of the compliance observations were found in the dimensions of 'waste control', 'control of establishment and equipment', and 'supply of raw food' 'Clean condition of refrigerator' item was $65\%$ out of the compliance that was the highest percent in this study. 'Notify and observance of heating/reheating temperature' was $45\%$ out of compliance. Items which were over $30\%$ out of compliance were 'sterilization of knifes and chopping boards in cooking', 'education of workers', 'maintain refrigerator temperature blow $5^{\circ}C$', and 'countermeasure of infection workers' In the results, most of the foodservice establishments were poorly managed in temperature control and cross-contamination. The important control points revealed in this study were preventing contamination, cooking temperature compliance, management of raw food and refrigerator. Therefore foodservice establishments should pay attention to education and training about important control points. The systematic sanitation management monitoring tool developed in this study can be effectively applied for conducting self-inspection and improving the sanitary conditions of their own foodservice operations.

Studies on the Nature and Pathogenicity of Nuclear Polyhedrosis Virus of the Fall Webworm, Hyphantria cunea (Drury) (흰불나방 핵다각체병바이러스의 성상과 병원성에 관한 연구)

  • Im Dae Joon;Hyun Jae Sun;Paik Woon Hah;Lim Jong Sung
    • Korean journal of applied entomology
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    • v.18 no.1 s.38
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    • pp.1-10
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    • 1979
  • An inclusion forming virus isolated from a fan webworm, Hyphantria cunea, in 1975 was identified as a nuclear polyhedrosis virus. With the virus isolated in Korea, it was considered that the virus would be one of the valuable microorganism in microbial control. In this connection, 1) the shape and size of the virus for identification, 2) susceptibility of the various instar larvae to the virus, 3) the effects of storage condition on the pathogenicity and the cross infection of the virus to the larvae of Bombyx mori were examined. The results are summarized as follows; 1. The polyhedron was tetrahedron or hexahedron of $2\mu$ in size and the rod-shaped virus particles consisting of $2\~14$ rods in a bundle were $330m{\mu}\times35m{\mu}$ in size. 2. The hexagonal nuclear polyhedra were found only in the nucleus of the midgut cells but were variable in size. 3. The $LD_{50}$ values for the various instar larvae of H. cunea were $8.377\times10^4\;PIBs/ml$ for the second, $4.974\times10^5\;PIBs/ml$ for the fifth instar larvae. The $LT_{50}values$ for $10^6\;PIBs/ml$ were 9.6 days for the second, 11.5 days for the third, 12.0 days for the fourth and 17 days for the fifth instar larvae. 4. The susceptibility of H. cunea to the nuclear polyhedrosis virus was greater in the first generation than in the second generation. 5. The effect of the storage conditions on the pathogenicity of the nuclear polyhedra was less in refrigerator $(5^{\circ}C)$ and in freezing $(-80^{\circ}C)$ than in room temperature $(18.5^{\circ}C)$, especially as air-dried polyhedra than as suspension. The pathogenicity of the polyhedra seemed to decrease by sunlight during storage as cadavers, since rather greater decrease in pathogenicity was found in sunny condition than in shady condition. 6. The effective spray concentration was $6.4\times10^7\;PIBs/ml$ in the field and its $LT_50$ values for the third and the fifth instar larvae were 4.8 days and 14.2 days, respectively. 7. No cross infections were found in the nuclear polyhedrosis virus between H. cunea and B. mori. larvae.

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Regulation of Tumor Neceosis Factor-${\alpha}$ Receptors and Signal Transduction Pathways

  • Han, Hyung-Mee
    • Toxicological Research
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    • v.8 no.2
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    • pp.343-357
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    • 1992
  • Tumor necrosis factor-${\alpha}$(TNF), a polypeptide hormone secreted primarily by activated macrophages, was originally identified on the basis of its ability to cause hemorrhagic necrosis and tumor regression in vivo. Subsequently, TNF has been shown to be an important component of the host responses to infection and cancer and may mediate the wasting syndrome known as cachexia. These systemic actions of TNF are reflected in its diverse effects on target cells in vitro. TNF initiates its diverse cellular actions by binding to specific cell surface receptors. Although TNF receptors have been identified on most of animal cells, regulation of these receptors and the mechanisms which transduce TNF receptor binding into cellular responses are not well understood. Therefore, in the present study, the mechanisms how TNF receptors are being regulated and how TNF receptor binding is being transduced into cellular responses were investigated in rat liver plasma membranes (PM) and ME-180 human cervical carcinoma cell lines. $^{125}I$-TNF bound to high ($K_d=1.51{\pm}0.35nM$)affinity receptors in rat liver PM. Solubilization of PM with 1% Triton X-100 increased both high affinity (from $0.33{\pm}0.04\;to\;1.67{\pm}0.05$ pmoles/mg protein) and low affinity (from $1.92{\pm}0.16\;to\;7.57{\pm}0.50$ pmoles/mg protein) TNF binding without affecting the affinities for TNF, suggesting the presence of a large latent pool of TNF receptors. Affinity labeling of receptors whether from PM or solubilized PM resulted in cross-linking of $^{125}I$-TNF into $M_r$ 130 kDa, 90 kDa and 66kDa complexes. Thus, the properties of the latent TNF receptors were similar to those initially accessible to TNF. To determine if exposure of latent receptors is regulated by TNF, $^{125}I$-TNF binding to control and TNF-pretreated membranes were assayed. Specific binding was increased by pretreatment with TNF (P<0.05), demonstrating that hepatic PM contains latent TNF receptors whose exposure is promoted by TNF. Homologous up-regulation of TNF receptors may, in part, be responsible for sustained hepatic responsiveness during chronic exposure to TNF. As a next step, the post-receptor events induced by TNF were examined. Although the signal transduction pathways for TNF have not been delineated clearly, the actions of many other hormones are mediated by the reversible phosphorylation of specific enzymes or target proteins. The present study demonstrated that TNF induces phosphorylation of 28 kDa protein (p28). Two dimensional soidum dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) resolved the 28kDa phosphoprotein into two isoforms having pIs of 6.2 and 6.1. The pIs and relative molecular weight of p28 were consistent with those of a previously characterized mRNA cap binding protein. mRNA cap binding proteins are a class of translation initiation factors that recognize the 7-methylguanosine cap structure found on the 5' end of eukaryotic mRNAs. In vitro, these proteins are defined by their specific elution from affinity columns composed of 7-methylguanosine 5'-triphosphate($m^7$GTP)-Sepharose. Affinity purification of mRNA cap binding proteins from control and TNF treated ME-180 cells proved that TNF rapidly stimulates phosphorylation of an mRNA cap binding protein. Phosphorylation occurred in several cell types that are important in vitro models of TNF action. The mRNA cap binding protein phosphorylated in response to TNF treatment was purifice, sequenced, and identified as the proto-oncogene product eukaryotic initiation factor-4E(eIF-4E). These data show that phosphorylation of a key component of the cellular translational machinery is a common early event in the diverse cellular actions of TNF.

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A Study on the Manufacture of the Artificial Cardiac Tissue Valve (생체판의 제작 및 실험)

  • Kim, Hyoung-Mook;Song, Yo-Jun;Sohn, Kwang-Hyun
    • Journal of Chest Surgery
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    • v.12 no.4
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    • pp.383-394
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    • 1979
  • Treatment of valvular heart disease with valve replacement has been one of the most popular procedures in cardiac surgery recently. Although, first effort was directed toward the prosthetic valve, it soon became popular that bioprosthesis, the valvular xenograft, was prefered in the majority cases. Valvular xenograft has some superiority to the artificial prosthetic valve in some points of thromboembolism and hemolytic anemia, and it also has some inferiority of durability, immunologic reaction and resistance to Infection. Tremendous efforts were made to cover the inferiority with several methods of collection, preservation, and valve mounting of the porcine valve or pericardium of the calf, and also with surgical technique of the valvular xenograft replacement. Auther has collected 320 porcine aortic valves immediately after slaughter, and aortic cusps were coapted with cotton balls in the Valsalva sinuses to protect valve deformity after immersion in the Hanks' solution, and oxidation, cross-linking and reduction procedures were completed after the proposal of Carpentier in 1972. Well preserved aortic valves were suture mounted in the hand-made tissue valve frame of 19, 21, and 23 mm J.d., and also in the prosthetic vascular segment of 19 mm Ld. with 4-0 nylon sutures after careful trimming of the aortic valves. Completed valves were evaluated with bacteriologic culture, pressure tolerance test with tolerane gauge, valve durability test in the saline glycerine mixed solution with tolerance test machine in the speed of 300 rpm, and again with pathologic changes to obtain following results: 1. Bacteriologic culture of the valve tissue in five different preservation method for two weeks revealed excellent and satisfactory result in view of sterilization including 0.65% glutaraldehyde preservation group for one week bacteriologic culture except one tissue with Citobacter freundii in 75% ethanol preserved group. 2. Pressure tolerance test was done with an apparatus composed of V-connected manometer and pressure applicator. Tolerable limit of pressure was recorded when central leaking jet of saline was observed. Average pressure tolerated in each group was 168 mmHg in glutaraldehyde, 128 mmHg in formaldehyde, 92 mmHg in Dakin's solution, 48 mmHg in ethylene oxide gas, and 26 mmHg in ethanol preserved group in relation to the control group of Ringer's 90 mmHg respectively. 3. Prolonged durability test was performed in the group of frame mounted xenograft tissue valve with 300 up-and-down motion tolerance test machine/min. There were no specific valve deformity or wearing in both 19, 21, and 23 mm valves at the end of 3 months (actually 15 months), and another 3 months durability test revealed minimal valve leakage during pressure tolerance test due to contraction deformity of the non-coronary cusp at the end of 6 months (actually 30 months) in the largest 23 mm group. 4. Histopathologic observation was focussed in three view points, endothelial cell lining, collagen and elastic fiber destructions in each preservation methods and long durable valvular tolerance test group. Endothel ial cell lining and collagen fiber were well preserved in the glutaraldehyde and formaldehyde treated group with minimal destruction of elastic fiber. In long durable tolerance test group revealed complete destruction of the endothelial cell lining with minimal destruction of the collagen and elastic fiber in 3 month and 6 month group in relation to the time and severity. In conclusion, porcine xenograft treated after the proposal of Carpentier in 1972 and preserved in the glutaraldehyde solution was the best method of collection, preservation and valve mounting. Pressure tolerance and valve motion tolerance test, also, revealed most satisfactory results in the glutaraldehyde preserved group.

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Serum Beta-2 Microglobulin: a Possible Marker for Disease Progression in Egyptian Patients with Chronic HCV Related Liver Diseases

  • Ouda, SM;Khairy, AM;Sorour, Ashraf E;Mikhail, Mikhail Nasr
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.17
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    • pp.7825-7829
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    • 2015
  • Background: Egypt has the highest prevalence of HCV infection in the world (~14.7%). Around 10-15% of HCV-infected persons will advance to cirrhosis within the first 20 years. The incidence of HCC is expected to grow in the next two decades, largely due to HCV related cirrhosis, and detection of HCC at an early stage is critical for a favorable clinical outcome. No simple reliable non-invasive marker has been available till now. B2M, a non-glycosylated polypeptide composed of 99 amino acids, is one of the components of HLA class I molecules on the surfaces of all nucleated cells. It has been reported that the level of serum B2M is elevated in patients with chronic hepatitis C and HCV-related HCC when compared to HCV-negative patients or healthy donors. Determining the clinical utility of serum B2M as a marker for disease progression in Egyptian patients with HCV related chronic hepatitis, cirrhosis and hepatocellular carcinoma was the aim of the present study. Materials and Methods: In this analytical cross sectional study 92 participants were included in 4 equal groups: Group (1) non cirrhotic chronic HCV; Group (2) HCV related liver cirrhosis; Group (3) HCC on top of HCV,; and Group (4) healthy controls. History taking, clinical examination, routine labs and abdominal ultrasound were conducted for all patients, PCR and Metavir scores for group (1) patients, and triphasic CT abdomen and AFP for Group (3) patients. B2M levels were measured in serum with a fully-automated IMX system. Results: The mean serum B2M level of Group (1) was $4.25{\pm}1.48{\mu}g/ml$., Group (2) was $7.48{\pm}3.04$, Group (3) was $6.62{\pm}2.49$ and Group (4) was $1.62{\pm}0.63$. Serum B2M levels were significantly higher in diseased than control group (p<0.01) being significantly higher in cirrhosis ($7.48{\pm}3.04$) and HCC groups ($6.62{\pm}2.49$) than the HCV group ($4.25{\pm}1.48$) (p<0.01). There was a significant correlation between B2M Level and ALK, total and direct bilirubin and INR (p<0.05), and a significant inverse correlation between B2M level and albumin, total proteins, HB andWBCS values (p<0.05). There was no significant correlation between B2M level and viral load or Metavir score, largest tumour size or AFP (p>0.05). The best B2M cut-off for HCV diagnosis was 2.6 with a sensitivity of 100%, a specificity of 92%, a positive predictive value (PPV) of 97% and a negative predictive value (NPV) of 100%. The best B2M cut-off for HCC diagnosis was 4.55 which yielded sensitivity, specificity, positive predictive value, negative predictive values of 74%, 62%, 39.5, 87.8% respectively (p-value <0.01) while best cut-off for cirrhosis was 4.9, with sensitivity 74 % and specificity 74%.The sensitivity for HCC diagnosis increased upon B2M and AFP combined estimation to 91%, specificity to 79%, NPV to 95% and accuracy to 83%. Conclusions: Serum B2M level is elevated in HCV related chronic liver diseases and may be used as a marker for HCV disease progression towards cirrhosis and carcinoma.

Endoparasitic Dinoflagellates, Amoebophrya spp. and their Host Dinoflagellates in Jinhae Bay, Korea (진해만에 출현하는 기생성 와편모류 Amoebophrya spp.와 숙주 와편모류)

  • Park, Jong-Gyu;Hur, Hyun-Jung;Coats, D. Wayne;Yih, Won-Ho;Ha, Na
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.12 no.4
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    • pp.359-369
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    • 2007
  • Amoebophrya is an obligate endoparasitic eukaryotic dinoflagellate infecting host species and eventually killing them within a short period. Because of its host specificity and significant impacts on population dynamics of host species, it has long been proposed to be a potential biological agent for controlling harmful algal bloom (HAB). For several decades, the difficulties of culturing host - parasite systems have been a great obstacle to further research on the biology of Amoebophrya but recent success of several culture systems reactivates this research field. In this study, as a preliminary work for understanding the impacts of Amoebophrya on the population dynamics of host species, semimonthly occurrence of infected host dinoflagellates by Amoebophrya spp. had been observed in Jinhae Bay for two years and with a host - parasite system cultivated, host specificity of Amoebophrya spp. on several dinoflagellates was tested. Amoebophrya spp. were observed in the cellular organelle and cytoplasm of several species including Akashiwo sanguinea, Ceratium fusus, Dinophysis acuminata, Heterocapsa triquetra, Oblea sp., Prorocentrum minimum, P. triestinum, Scrippsiella spinifera, and S. trochoidea. Among them two host - parasite systems for an athecate dinoflagellate, A. sanguinea, and for a thecate dinoflagellate, H. triquetra, had been able to be successfully established as laboratary cultures. Cross-infection tests for 6 species of dinoflagellates in which Amoebophrya was observed or had been reported to exist confirmed high preference for host species of the parasite. Through the continuous research on Amoebophrya occurring in Korean coastal waters, we need to maintain various host - parasite culture systems, which will be very helpful for understanding its ecological role in marine food webs and for applying the species to biologically control harmful algal blooms.