• The Plant Pathology Journal
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• v.31 no.3
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• pp.203-211
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• 2015

Maize is the dominant cereal crop produced in the US. One of the main fungal pathogens of maize is Fusarium verticillioides, the causative agent of ear and stalk rots. Significantly, the fungus produces a group of mycotoxins - fumonisins - on infested kernels, which have been linked to various illnesses in humans and animals. Nonetheless, durable resistance against F. verticillioides in maize is not currently available. In Texas, over 2.1 million acres of maize are vulnerable to fumonisin contamination, but understanding of the distribution of toxigenic F. verticillioides in maize-producing areas is currently lacking. Our goal was to investigate the genetic variability of F. verticillioides in Texas with an emphasis on fumonisin trait and geographical distribution. A total of 164 F. verticillioides cultures were isolated from 65 maize-producing counties. DNA from each isolate was extracted and analyzed by PCR for the presence of FUM1- a key fumonisin biosynthesis gene - and mating type genes. Results showed that all isolates are in fact F. verticillioides capable of producing fumonisins with a 1:1 mating-type gene ratio in the population. To further study the genetic diversity of the population, isolates were analyzed using RAPD fingerprinting. Polymorphic markers were identified and the analysis showed no clear correlation between the RAPD profile of the isolates and their corresponding geographical origin. Our data suggest the toxigenic F. verticillioides population in Texas is widely distributed wherever maize is grown. We also hypothesize that the population is fluid, with active movement and genetic recombination occurring in the field.

• Mycobiology
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• v.46 no.2
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• pp.92-100
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• 2018

The filamentous Ascomycota Colletotrichum gloeosporioides sensu lato is a fungus that has been reported worldwide as a causal agent of anthracnose disease in avocado and other crops. In Mexico, this species affects fruits from an early stage of development in the orchard until the post-harvest stage. Although fungicides are continuously applied to control Colletotrichum species, pericarp cankers and soft rot mesocarp in fruits are still frequently observed. Considering the lack of a precise description of the causative agent, the aim of the current study was to determine the pathogens involved in this symptomatology. Twenty-four isolates were consistently obtained from the pericarp of avocado fruits cv. "Hass" collected in the central avocado-producing area of Mexico. Morphological features such as colony growth, conidia size, and mycelial appressorium were assessed. Bayesian multilocus phylogenetic analyses were performed using amplified sequences of the internal transcribed spacer region of the nuclear ribosomal DNA; actin, chitin synthase, glyceraldehyde-3-phosphate dehydrogenase partial genes; and APn2-Mat1-2 intergenic spacer and mating type Mat1-2 partial gene from the nine selected isolates. In addition, fruits were inoculated with a conidial suspension and reproducible symptoms confirmed the presence of Colletotrichum fructicola in this area. This pathogenic species can now be added to those previously reported in the country, such as C. acutatum, C. boninense, C. godetiae, C. gloeosporioides, and C. karstii. Disease management programs to reduce the incidence of anthracnose should include C. fructicola to determine its response to fungicides that are routinely applied, considering that the appearance of new species is affecting the commercial quality of the fruits and shifting the original population structure.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.2
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• pp.125-127
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• 2010

The coexistence of aspergillosis and squamous cell carcinoma (SCC) in the maxillary sinus was very rare. To our knowledge, this is the second report of coexistent SCC and aspergillosis in the maxillary sinus. A 58-year-old man underwent surgery for unilateral maxillary sinus infection with oroantral fistula. In the surgical specimen, SCC and aspergillosis were co-detected with routine and immunohistochemical stainings. Moreover, human papillomavirus 18 (HPV-18) was detected by polymerase chain reaction in the sinus specimen. The patient was re-operated with subtotal maxillectomy and has been followed up for two years without any evidence of recurrence or metastasis. Although it is not understood how aspergillosis could induce carcinoma formation, the chronic inflammation caused by prolonged fungal infection might be carcinogenic. Moreover, HPV-16 and -18 were another causative pathogens of SCC in the head and neck region. We recommend careful examination, including preoperative cytology, in patients with maxillary sinus fungal infections because of the potential for cancer development.

• Childhood Kidney Diseases
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• v.10 no.2
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• pp.182-191
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• 2006

Purpose : We studied the degree of changes in antibiotic sensitivity toward causative organisms, prevalence and clinical manifestations of extended-spectrum $\beta$-lactamase(ESBL)-producers of urinary tract infection(UTI) for a period of three years. This serves to provide useful information in selecting adequate drugs for the treatment of UTI. Methods : We recruited 137 patients who grew more than $10^5$ CFU/mL in their urine culture among 250 patients who visited and were admitted to Handong University's Sunlin Hospital for UTI treatment from January 2003 to December 2005. We retrospectively analyzed the data from the medical records. Results : The common pathogenic organisms were Escherichia coli(65.0%), Klepsiella pneumoniae(14.0%), Enterococcus faecalis(5.8%) and Proteus vulgaris(2.9%) in consecutive order. The prevalence of ESBL-producers among isolated E. coli and K. pneumoniae was 4.5%(4 cases) and 14.3%(2 cases), respectively. The antibiotic sensitivity rates of E. coli were relatively high to amikacin(100%), imipenem(100%), ceftriaxone(95.5%) and tobramycin(91.4%) while relatively low to TMP/SMZ(55.4%), ampicillin/sulbactam(29.4%) and ampicillin(24.2%). Conclusion : The use of ampicillin, ampicillin/sulbactam and TMP/SMZ, which have been the first choices in the treatment of UTI, should be reconsidered due to the low sensitivity rates towards these antibiotics. Due to the high incidence and antibiotic tolerance of ESBL that might have risen from the development of new antibiotics and increased antibiotic use, it is necessary to consider changing the standard antibiotics that have been used in the treatment of UTI.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.1
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• pp.45-51
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• 2014

Scuticociliates are regarded as serious pathogens in marine aquaculture worldwide. In Korea, they cause mass-mortalities in fish such as the commercially important olive flounder Paralichthys olivaceus. In particular, mixed infections of scuticociliates with pathogenic bacteria have been commonly reported. During efforts to identify natural marine-algae derived products that possess anti-bacterial and anti-scuticociliate properties, we found that an 80% methanolic extract of the red alga Polysiphonia morrowii Harvey exhibits both anti-scuticociliate activity against Miamiensis avidus, which is a major causative agent of scuticociliatosis, and anti-bacterial activities against fish pathogenic bacteria. Activity-guided fractionation and isolation of the 80% methanolic extract of P. morrowii yielded three bromophenols, which were identified as 3-bromo-4,5-dihydroxybenzyl methyl ether (1), 3-bromo-4,5-dihydroxybenzaldehyde (2) and urceolatol (3) based on spectroscopic analyses. 3-bromo-4,5-dihydroxybenzyl methyl ether (1) showed the highest anti-bacterial and anti-scuticociliate activities, with a minimal inhibitory concentration (MIC) of $62.5{\mu}g/mL$ (against Vibrio anguillarum) and minimal lethal concentration (MLC) of 62.5 ppm (in seawater). Investigations of the anti-bacterial and anti-scuticociliate activities of seventeen bromophenol derivatives, including the three isolated natural bromophenols, showed that the existence of an electron donating group or atom with a non-covalent electron pair at $C_4$ of the 2-bromophenol structure may be important in anti-scuticociliate activity. These findings suggest that the extract and bromophenol derivatives of P. morrowii may provide useful alternatives in aquaculture anti-scuticociliate therapies.

• Biomedical Science Letters
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• v.13 no.1
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• pp.47-53
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• 2007

Due to wide abuse of antibiotics both in human and livestock use, the advent and spread of multidrug resistant (MDR) pathogens becomes a serious health problem all over the world. Since the development of new antibiotics is at a standstill in pharmaceutical industry, the choice of therapeutic antibiotics is getting narrower. In this study, in an effort to search new antibiotics, the antimicrobial activity of Paenibacillus DY1 isolated from Korean soil was characterized on its growth inhibition spectrum against various health threatening MDR strains, with its stability and chemical structure. Extracellular culture filtrate of Paenibacillus DY1 effectively inhibits the growth of all the tested MDR enteropathogenic Eshcherichia coli, enterohemolytic E. coli, and enterotoxigenic E. coli strains, at a similar level to that on the nonresistant control E. coli strains. It showed significant growth inhibition effect against the causative agents of class one legal communicable disease, MDR Salmonella typhi, MDR Salmonella paratyphi A, food poisoning bacteria, MDR Salmonella typhimurium, and other MDR Salmonella spp. The growth of all of 10 different MDR Shigella spp. strains and 6 different Vibrio spp. strains tested was also inhibited. The antimicrobial activity of Paenibacillus DY1 was well preserved after heat treatment, and was also stable in both alkaline and acidic environment. The antimicrobial activity was partially purified with Diaion HP20 column and TLC. By NMR study, the putative structure of the activity was postulated as an alkane having hydroxyl groups.

• Journal of Food Hygiene and Safety
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• v.11 no.4
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• pp.277-285
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• 1996

Retrospective study on the comparison of outbreaks of food poisoning for food hygiene in Korea and Japan. The average value of morbidity rate by year in Korea during the period of 1971 to 1992 was 2.9 per 100,000 population, and that of Japan was 29.1. The mean value of mortality rates in case of food poisoning by year in Korea was 2.33%, and that of Japan was 0.07%. When compared the rates of morbidity and mortality between Korea and Japan during the same period, the morbidity rates of Japan were much higher than those of Korea (p<0.01). However, mortality rate of patients in Korea were much higher then those of Japan(p<0.01). Resulting from comparative observation of food poisoning by preparing facilities between Korea and Japan. The highest list the places where the outbreaks occurred was home-made foods accounted for 48.8% of the total cases in Korea and that of Japan was restaurants accounted for 33.0%. Causative foods in Korea, the most common incrimination vehicles were seafood, meat and animal products and grain and vegetables, including mushroom. However, in the case of the common incrimination vehicles Japan were unknown and other foods, seafood, vegetables and meat and animal products etc.. Food poisoning of pathogenic substance in Korea were 60.9% of bacterial food poisoning of the total cases showing that Vibrio species, Salmonella spp., Staphylococcus spp., pathogenic E. coli, Clostridium spp. and other spp. were 33.3%, 26.2%, 16.3%, 5.3%, 0.4% and 18.5%, respectively. On the other hand, in Japan, major causes were Vibrio spp. (45.7%), Staphylococcus spp. (23.7%), Salmonella spp. (16.8%), pathogenic E. coli (3.8%), Clostridium spp. (0.2%) and other spp. (9.6%).

• Biomedical Science Letters
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• v.20 no.2
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• pp.77-84
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• 2014

Periodic analysis of local epidemiologic data of prevalent pathogens of blood culture can provide clinicians with relevant information to guide empirical antibiotic therapy. In this study, we analyzed a pattern of change of causative microorganisms and antimicrobial resistance at a tertiary medical center in Chungcheong province from 2003 to 2012, retrospectively. Of 70,258 blood specimens cultured, 6,063 (8.6%) were positive. Among the positive isolates, 95.9% were aerobic or facultative anaerobic bacteria, 0.1% were anaerobes, and 3.9% were fungi. Coagulase-negative Staphylococci (CoNS) (32.9%), Escherichia coli (16.7%), Staphylococcus aureus (9.1%), Klebsiella pneumoniae (6.4%), and ${\alpha}$-hemolytic Streptococcus (5.9%) were commonly isolated bacteria, and Candida albicans (1.4%) was the most commonly isolated fungi. Enterococcus faecium progressively increased but Streptococcus pneumoniae, Acinetobacter baumannii and Proteus species gradually decreased over a period of 10 years. The multidrug-resistant microorganisms such as methicillin-resistant S. aureus (MRSA), vancomycin-resistant enterococci (VRE), cefotaxime-resistant E. coli, imipenem-resistant Pseudomonas aeruginosa (IRPA) and imipenem-resistant A. baumannii (IRAB), were significantly increased. Therefore, there is a need for a more strict control of antibiotics and a more updated guideline for the treatment of bloodstream infection.

• Korean Journal of Veterinary Service
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• v.24 no.1
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• pp.83-88
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• 2001

It is impotent to identify the causative agents of abortion in equine for minimizing the loss of breeding costs in equine Industry. Recently, the abortion has often occurred in equine herds and thus the purpose of the study was aimed at the identification of equine herpesvirus-1, one of the frequent pathogens to abortion, using polymerase chain reaction. Six fetuses to be aborted at nine to ten months in pregnancy reared in six herds were used in the study. Two primers in the PCR were made from glycoprotein B gene of EHV-1. The primers specific for EHV-1 amplified 1880 bp of PCR products from DNA extracts from thorax fluids, livers, lungs, and spleens of four in six aborted fetuses. Consequently, PCR could be applied to diagnose the abortion of EHV-1 and also confirmed to play a major role of the viral pathogen associated with equine abortion in Jeju island.

• Korean Journal of Veterinary Research
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• v.41 no.2
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• pp.197-202
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• 2001

Although several methods have been developed and applied to control swine respiratory diseases, the disease induces severe economic impact to swine industry worldwide. As one of the new trials, application of egg yolk antibody(IgY) was attempted for the purposes and immune response in sera and egg yolk was analysed with ELISA in previous study. In this study, immunological specificity of the IgY was analysed by Western blot analysis. In the analysis of causative agents of atrophic rhinits, B bronchiseptica and P multocida 4D, proteins of 33, 40, 43, 67 and 141 kDa were specifically reacted with IgY Also, 40 and 110 kDa proteins were identified as the major immunogens in P multocida 3A. In A pleuropneumoniae serotypes 2 and 5, 40 kDa and 47 kDa proteins were found to be the major reactive ones. These results suggested that egg yolk antibodies from immunized hens was specific with antigens injected into hens and partially purified antigens, outer membrane proteins and dermonecrotic toxin, were more effective than bacterin for the production of specific antibody.