• 대한수의학회지
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• 제51권1호
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• pp.29-35
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• 2011

Lack of hygiene and puerperal mastitis are common causes of bacterial diseases in nursing neonates. The aim of this study was to isolate microorganisms from milk samples of healthy female Jindo dogs with suckling puppies and to investigate antimicrobial susceptibility against the isolated bacteria. Milk samples were collected from 120 udders of 12 lactating Jindo dogs that were 2~4 years old without any clinical diseases including mastitis. Bacteria were isolated from 64 milk samples (53.3%), either singly (76.6%) or in combination (23.4%). Staphylococcus (S.) spp. was the most common microorganisms (74.7%) isolated from canine milk, followed by Haemophillus spp. (10.9%), Streptococcus spp. (9.6%), Gardnerella spp. (2.4%) and Moraxella spp. (2.4%). The most frequently isolated organism was S. warneri (31.3%). Antimicrobial susceptibility of these bacteria was tested with 17 antimicrobial agents by Kirbyand Bauer standardized disc diffusion method. Results indicated that bacteria isolated from healthy canine milk were mostly susceptible to amoxicillin-clavulanic acid, cephalothin and ceftiofur, but were resistant to erythromycin, neomycin and tetracycline.

• Toxicological Research
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• 제24권4호
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• pp.321-328
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• 2008

Smoke flavors based on the thermal decomposition of wood have been applied to a variety of food products as an alternative for traditional smoking. Despite its increasing use, the available genotoxicity data on wood smoke flavors (WSF) are still controversial. Thus, potential genotoxic effects of WSF in four short-term in vitro genotoxicity assays were investigated, which included the Ames assay, chromosomal aberration assay, micronucleus test and the alkaline comet assay. WSF did not cause any mutation in the Ames assay using five tester strains at six concentrations of 0.16, 0.31, 0.63, 1.25, 2.5 and 5 ${\mu}l/plate$. To assess clastogenic effect, the in vitro chromosomal aberration assay was performed using Chinese hamster lung cells. No statistically significant increase in the number of metaphases with structural aberrations was observed at the concentrations of 1.25, 2.5, and 5 ${\mu}l/ml$. The in vitro comet assay and micronucleus test results obtained on L5178Y cells also revealed that WSF has no genotoxicity potential, although there was a marginal increase in micronuclei frequencies and DNA damage in the respective micronucleus and comet assays. Taken together, based on the results obtained from these four in vitro studies, it is concluded that WSF is not a mutagenic agent in bacterial cells and causes no chromosomal and DNA damage in mammalian cells in vitro.

• Asian-Australasian Journal of Animal Sciences
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• 제15권5호
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• pp.751-756
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• 2002

A study was carried out to evaluate the incidences and causes of bovine mastitis in Tanzanian shorthorn zebu (Bos indicus) in the traditional sector and crossbred cows (Bos taurus${\times}$Bos indicus) in the dairy ranching sector, both found under the extensive range management system. Management practices were evaluated through a survey study using structured questionnaires. A total of 120 lactating cows (60 cows from each sector) were screened for the disease using the California Mastitis Test (CMT). Confirmatory tests used for infected cows included; the Direct Microscopic Somatic Cell Count (DMSCC), culture, bacteriological and biochemical laboratory assays. Survey results showed that management practices were generally very poor in both sectors with 84% of the surveyed herds being kept and milked under very unhygienic environmental conditions. The level of infection was higher in the crossbred cows (5% clinical and 38.3% sub-clinical mastitis) and lower in the zebu cows with only sub-clinical mastitis (23.3%). Crossbred cows had (p<0.05) higher somatic cell counts than zebu cows. The four highest-ranking bacterial isolates in order of importance were Staphylococcus aureus, Escherichia coli, Streptococcus agalactiae and Bacillus spp. It was concluded that bovine mastitis under the extensive management system in Tanzania was a result of poor management practices and that zebu cows were more resistant to the diseases than crossbred cows.

• Asian Pacific Journal of Cancer Prevention
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• 제16권4호
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• pp.1315-1319
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• 2015

The fact that long-term use of proton pump inhibitors (PPIs) aggravates corpus atrophic gastritis in patients with Helicobacter pylori infection has been proven clinically and experimentally. Corpus atrophic gastritis is a known risk factor for gastric cancer. Therefore, gastric neoplasia might be associated with the long-term use of PPIs. One of the causes of worsening corpus atrophic gastritis, leading to the development of adenocarcinoma, might be bacterial overgrowth under conditions of hypochlorhydria. The production of potentially carcinogenic N-nitrosocompounds by nitrosating organisms under conditions of hypochlorhydria might be associated with carcinogenesis. Interactions between bile acids, pH, and H. pylori might also contribute to carcinogenicity, especially in patients with gastro-esophageal reflux disease (GERD). The concentration of soluble bile acids, which have bactericidal or chemorepellent properties toward H. pylori, in gastric contents is considerably higher in patients undergoing continuous PPI therapy than in healthy individuals with normal acid production. Under these circumstances, H. pylori might colonize the stomach body rather than the pyloric antrum. Hypergastrinemia induced by PPI administration might promote the development of gastric cancer. Because the main cause of corpus atrophic gastritis is H. pylori infection, and not PPI administration, H. pylori infection should be eradicated before starting long-term PPI therapy.

• The Plant Pathology Journal
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• 제20권1호
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• pp.52-57
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• 2004

Sclerotinia sp. (isolate BWC98-105) causes stem blight and root rot in Leghum sp., and is presently being evaluated as a potential mycoherbicide for the control of Trifoliorium repens. Bioassays have shown that Sclerotinia sp. produces phytotoxic substance which is biologically active against T. repens. Two biologically active compounds, designated as compoundsI and II, were produced in vitro from the culture filtrate of BWC98-105 isolate Sclerotium sp. Compounds I and II were purified by means of liquid-liquid extraction and $C_{18}$ open column chromatography (300 ${\times}$ 30 mm, i.d). To determine the purity, the purified compounds were analyzed by RP-HPLC. The analytical RP-HPLC column was a TOSOH ODS-120T (150 ${\times}$ 4.6 mm i.d, Japan), of which the flow rate was set at 0.7 mL/min using the linear gradient solvent system initiated with 15 % methanol to 85 % methanol for 50 min with monitoring at 254 nm. Under these RP-HPLC conditions, compounds I and II eluted at 3.49 and 4.13 min, respectively. Compound II was found to be most potent and host specific. However, compound I had a unique antibiotic activity against phytopathogenic bacteria like bacterial leaf blight (Xanthomonas oryzae) on rice, where it played a less important role in producing toxicity on T. repens. No toxin activity was detected in the water fraction after partitioning with several organic solvents. However, toxin activity was detected in the ethyl acetate and butanol fractions. In the leaf bioassay using compound II, the disease first appeared within 4-5 h as water soaked rot, which subsequently developed into well-defined blight affecting the whole plant.

• Journal of Chest Surgery
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• 제11권4호
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• pp.516-522
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• 1978

In spite of recent improvement of the medical and surgical treatments, there are many significant problems in the management of thoracic empyema. This is a clinical analysis of 49 cases of thoracic empyema who underwent lung decortication for a period of 6 years and 5 months extending from May, 1972 to Aug. 1975. The following results were obtained: Male to female ratio was 2. S to 1. The age ranged between Sand 69, bnt was mostly 2r.d and 5th decade. The underlying diseases were pulmonary tuberculosis (30 cases, 61. 1 SO, , ), posttraumatic hemothorax (7 cases, 14.396). pneumonia (6 cases, 12.2%), lung abscess (2 cases, 4.2%), paragonimiasis (2 cases, 4.2%). spontaneous pneumothorax (1 case, 2.1%), and unknown origin (1 case, 2.1%). In 13 cases (26.5%), positive bacterial growth on culture was reported. There were single infection in 11 cases and mixed infection in 2 cases. The organisms grown were Staphylococcus, alpha-hemolytIc Streptococcus, Alkaligenes fecalis, Escherichia coli, Pseudomonas, SerratIa, Enterobacter agglomerans, and Enterococcus in order of frequency. Staphylococcus, Streptococcus, and Serratia were sensitive to several different kinds of antibiotics. But Pseudomonas, Escherichia co:i, and Enterococcus were sensitive to only one or two antibiotics. Leukocytosis was observed In acute empyema, but not in chronic empyema. Hemoglobin and hematocrit were all within normal limits. Preoperative liver function tests were within normal limits in most of the cases. In 49 cases, lung decortication alone was performed in 40 cases (S1. 696), and for the remaining 9 cases (1S. 4%), additional surgical procedures were necessary, i. e., lobectomy (6cases). partial thoracoplasty (2 cases), and lobectomy & partial thoracoplasty (1 cases). The results of lung decortication in thoracic empyema were goed. 38 cases (77.5%) healed with no complication, and 10 cases (20.4%) were complicated by bleeding, wownd infection, pleural infection, chondritis, and psychosis. These complications resolved ultimately leaving no sequelae. One death was recorded (2.1%), and the causes of death were postoperative pleural infection, sepsis and hepatic insufficiency.

• Journal of Chest Surgery
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• 제16권4호
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• pp.498-505
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• 1983

It has been over 20 years since successful operations of Cardiac valves at the Department of Thoracic and Cardiovascular surgery, college of medicine, Yonsei University. About six hundreds of patients with severely symptomatic valvular heart disease have had valve operations with complete loss or sharp decrease in their cardiac symptoms since 1956. As the number of cardiac patient increases, reoperation on valves assumes greater importance. To define the group of patients undergoing reoperations on valves and the factors influencing their survival, we have reviewed our experiences of the reoperation on valves at the Yonsei University, Severance Hospital. This is a report of 29 cases which was undergone secondary or more surgery for valvular heart disease from 1966 to 1983. The primary operations includes 159 cases of open heart surgery from 1966 to 1975 and 476 cases from 1976 to march, 1983. The secondary operations are classified into groups of secondary valvuloplasty or valvotomy [8 cases], prosthetic valve replacement following valvuloplasty or valvotomy [14 cases] and prosthetic valve rereplacement [2 case] for such as calcification, degeneration and perforation of the cusps and paravalvular leakage, of the bioprosthetic valves. The leading indication for reoperation of mitral valve was restenosis or stenoinsufficiency, The indications of aortic valve replacement was active bacterial endocarditis, medically uncontrollable prosthetic endocarditis or paravalvular leakage. Overall death rate of the reoperation was 17.4% [5 death among the 29 patients] and the leading causes of death were myocardial failure, arrhythmia, cerebral embolism, acute renal failure due to low output syndrome. And it was followed by sepsis associated with active prosthetic endocarditis. The death rate of reoperation was 4.3% in the elective cases except urgent cases and the death rate of overall cardiac valve except reoperation cases was 4.1% in the last two years. Although the general mortality of reoperation was high, both mortality rates were comparable except emergency cases due to urgent preoperative patient’s condition.

• KSBB Journal
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• 제32권1호
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• pp.22-28
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• 2017

Bacteria are among the most common causes of severe diseases in both plants and animals. Salmonella spp. has deleterious effects and is the cause of various transmittable diseases. Because of strains resistivity, side effects and high prices of synthetic antibiotics, it has become essential to explore safe and economical natural sources of antibiotics. In this study, growth inhibitory effects of natural antibiotics present in crude extracts of Galla rhois, Thujae semen, Paeonia japonica, and Armeniacae semen were investigated both in vivo and iv vitro. Ethanol extracts of the above-mentioned plants were prepared and tested against seven serovars of Salmonella and Escherichia coli by disc diffusion method. In addition, the antibacterial effects of the plant extracts were determined in vivo using ducks as model animals. Reverse transcription-polymerase chain reaction was performed using blood and fecal samples of control, infected, and treated groups of the ducks to determine the gene expression levels of the bacteria. Our results confirmed that the Galla rhois ethanol extract had the highest antibacterial activity among the plant extracts when they were used individually. However, the Galla rhois, Thujae semen, and P. japonica ethanol extracts showed stronger antibacterial effects against all the bacterial species used when the extracts were combined at a ratio of 3:3:2, respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제31권8호
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• pp.1073-1077
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• 2018

Nitrite plays a major role in inhibiting the growth of foodborne pathogens, including Clostridium botulinum (C. botulinum) that causes botulism, a life-threatening disease. Nitrite serves as a color-fixing agent in processed meat products. However, N-nitroso compounds can be produced from nitrite, which are considered as carcinogens. Thus, consumers desire processed meat products that contain lower concentrations (below conventional concentrations of products) of nitrite or no nitrite at all, although the portion of nitrite intake by processed meat consumption in total nitrite intake is very low. However, lower nitrite levels might expose consumers to risk of botulism poisoning due to C. botulinum or illness caused by other foodborne pathogens. Hence, lower nitrite concentrations in combination with other factors such as low pH, high sodium chloride level, and others have been recommended to decrease the risk of food poisoning. In addition, natural compounds that can inhibit bacterial growth and function as color-fixing agents have been developed to replace nitrite in processed meat products. However, their antibotulinal effects have not been fully clarified. Therefore, to have processed meat products with lower nitrite concentrations, low pH, high sodium chloride concentration, and others should also be applied together. Before using natural compounds as replacement of nitrite, their antibotulinal activities should be examined.

• 한국응용곤충학회지
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• 제39권3호
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• pp.193-197
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• 2000

Wolbachia는 몇몇 곤충류에 공생하는 세포내 공생세균으로서 수직 감염되며, 숙주의 세포질 불화합성, 단위생식, 자성화 등을 유도한다. 현재까지 알려진 Wolbachia는 비병원성이지만 돌연변이인 popcorn은 숙주인 초파리(Drosophila melanogaster)에 수직 감염되어 성충의 조직괴사와 조기 사망 등의 병원성을 나타낸다. Popcorn에 감염된 초파리는 알과 유충 발육기간이 연장되고, 번데기 기간은 단축되는 경향을 보이며, 성충의 수명이 단축되었다. 또한 비병원성 Wolbachia에 감염된 경우보다 산란율은 15%, 부화율은 80% 수준으로 감소하였고, 용화율은 67%, 우화율은 65%에 불과하였다. Popcorn과 비병원성 Wolbachia간의 교배에서 감염된 초파리는 모두 산란수의 감소와 차세대 부화율, 용화율, 우화율 등의 감소를 초래하였으며, popcorn에 감염된 초파리의 특성을 나타냈다. Wolbachia에 감염되지 않은 초파리와의 교배에서 popcorn 감염 초파리가 수컷인 경우 Wolbachia가 검출되지는 않았다. 따라서 popcorn은 초파리에서 모체 전염되지만, 세포질 분화합성은 유도하지 않으며, 초파리의 초기발육의 지연, 생식의 저하, 성충수명의 단축을 야기하는 등 병원성을 나타냈다.