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Sir Arnold Theiler and the discovery of anaplasmosis: A centennial perspective
2009
Palmer, G.H.(Washington State University School for Global Animal Health Department of Veterinary Microbiology and Pathology)
Sir Arnold Theiler's research in 1908/09 led to the discovery of the first rickettsial pathogen, Anaplasma marginale, and set the stage for his development and implementation of an effective live vaccine based on a less virulent strain, A. marginale ss. centrale. His 1910 report, describing A. marginale, is among the classic monographs in infectious disease research, presenting not only observations in exacting detail but also highlighting the deductive reasoning leading to association of a new pathogen with a specific disease. With a centennial perspective and both conceptual frameworks and molecular tools unimaginable in Theiler's time, the significance of several observations in the original report- cyclic bacteremia, strain superinfection, and taxonomic position-is now clear and highlight the broad applicability of key principles of pathogen biology.
Afficher plus [+] Moins [-]The proteasome inhibition enhances apoptosis by P53 expression and the dissipation of mitochondrial transmembrane potential in TRAIL-resistant lung cancer cells
2009
Seol, J.W., Chonbuk National University, Jeonju, Republic of Korea | Park, S.Y., Chonbuk National University, Jeonju, Republic of Korea
The ubiquitin-proteasome mediated protein degradation pathway plays an important role in regulating both cell proliferation and cell death. Proteasome inhibitors are well known to induce apoptosis in various human cancer cell lines. We investigated the effect of combined treatment with proteasome inhibitor and TRAIL, and a possible mechanism of the enhancing apoptosis by the both treatment, on TRAIL-resistant non-small cell lung cancer. A549 cells were exposed to the N-Acetyl-Leu-Leu-Norleu-al(ALLN) as a proteasome inhibitor and then treated with recombinant TRAIL protein. In A 549 cells under proteasome inhibition conditions by pretreatment with ALLN, TRAIL treatment significantly decreased cell vibility compared to that ALLN and TRAIL alone treatment. Also, the both treatment induced cell damage through DNA fragmentation and p53 expression. In addition, the combined treatment of both markedly increased caspase-8 activation, especially the exposure for 2h, and Bax expression and induced the dissipation of mitochondrial transmembrane potential in A549 cells. Taken together, these findings showed that proteasome inhibition by ALLN enhanced TRAIL-induced apoptosis via DNA degradation by activated P53 and mitochondrial transmembrane potential loss by caspase-8 activation and bax expression. Therefore, our results suggest that proteasome inhibitor may be used a very effectively chemotherapeutic agent for the tumor treatment, especeally TRAIL-resistant tumor cell.
Afficher plus [+] Moins [-]A 90-day repeated-dose oral toxicity study on Chelidonium majus extract in Fischer 344/N rats
2009
Kim, D.H., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Zhang, H.S., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Kim, K.H., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Kang, S.C., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Kim, H.S., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Gil, K.H., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Kong, K.H., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Ahn, T.H., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Bae, J.S., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Go, H.K., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Kim, K.H., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Park, C.K., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Lee, H.K., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Song, S.W., Preclinical Research Center, ChemOn, Yongin, Republic of Korea | Han, Z.Z., Preclinical Research Center, ChemOn, Yongin, Republic of Korea
This study was performed to evaluate repeated-dose oral toxicities of Chelidonium majus extract in Fischer 344/N rats. Chelidonium majus extract was administered orally to rats at dose levels of 0, 25, 74, 222, 666 and 2,000 mg/kg/day. Each group consisted of 10 rats of each gender. The Chelidonium majus extract was given once a day, 5 times a week, for 90 day repeatedly. This study was conducted in accordance with the Protocol of Korea National Toxicology Program (issued by National Institute of Toxicological Research) and The Standards of Toxicity Study for Medicinal Products (issued by Korea Food and Drug Administration). In the present study, There were no toxicologically significant changes in mortality, clinical signs, body weight gains, ophthalmoscopy, urine analysis, hematology, serum biochemistry, necropsy findings, organ weights, histopathology, estrus cycle and sperm examination of all animals treated with Chelidonium majus extract. These results suggest that the oral no observed adverse-effect level of the test item, Chelidonium majus extract, in rats is higher than 2.000 mg/kg/day in both genders. The target organs were not established.
Afficher plus [+] Moins [-]Efficacy of aromatherapy for the treatment of otitis externa in dogs
2009
Kim, S.H., Chungnam National University, Daejeon, Republic of Korea | Kim, S., Gyeongsang National University, Jinju, Republic of Korea | Jun, H.K., Chungnam National University, Daejeon, Republic of Korea | Kim, D.H., Chungnam National University, Daejeon, Republic of Korea
This study examined the therapeutic effects of aromatherapy for the treatment of otitis externa in dogs. Eleven dogs with otitis externa were examined. The control group (5 dogs) was treated with susceptible antibiotics, and the experimental group (6 dogs) was treated with aroma-oil applied topically to the ear canal. The aroma-oil contained 10 ml sweet almond oil, 0.3 ml bergamot oil, 0.2 ml lavender oil, 0.1 ml tea tree oil and 0.1 ml roman chamomile oil. The blended aroma-oil (0.1 ml) was applied to the ear canal twice daily for 2 weeks. The authors examined the changes in the clinical signs, bacterial count in discharges, total WBC count and neutrophil/lymphocyte ratios in the two groups. The bacterial cell counts in the experimental group were significantly lower at one (p less than 0.01) and two weeks (p less than 0.05) after treatment than the control group. These results suggest that aromatherapy is an effective and practical treatment for otitis externa in dogs.
Afficher plus [+] Moins [-]A basic study on the animal welfare evaluation in Korean zoos
2009
Cho, K.U., Children's Grand Park, Seoul Metropolitan Facilities Management Corporation, Seoul, Republic of Korea | Choe, B.I., The Catholic University of Korea, Seoul, Republic of Korea | Kim, H.Y., Konkuk University, Seoul, Republic of Korea | Han, J.S., Konkuk University, Seoul, Republic of Korea | Kim, J.S., Konkuk University, Seoul, Republic of Korea
The concept about zoo is changing from the animal exhibition which simply contained the animals to the ecological zoo which has the function of preserving the animal species. At the central point of maintaining such role, the basic principle called the animal welfare lies obviously. Korea has applied the animal welfare principles such as carrying out the enrichment in the zoos since 2003, but there has not been any institutional device to evaluate and examine the application of the animal welfare so far. This study aims to confirm the level of animal welfare in Korea and suggest a developmental direction. For the purpose of the study, 12 zoos in Korea were evaluated according to 68 evaluating categories. 'Five Principles of Animal Welfare' in the Secretary of State's Standards of Modern Zoo Practice were selected and carried out as the evaluation categories, and the result, from the highest to lowest score given, was 'provision of food and water', 'provision of protection from fear and distress', 'provision of health care', 'provision of an opportunity to express most normal behaviours', and 'provision of a suitable enrichment' with the overall score of the entire Korean zoos being 2.86 (± 0.56). It was also confirmed that in order to improve the animal welfare of the Korean zoos, the animal management system must be standardized and organized. The evaluation and feedback, the active practice of animal welfare and its legislative support should be provided to establish an effective institutional device as well.
Afficher plus [+] Moins [-]Studies on characteristic analysis of Streptomyces fradiae isolated from soil and effect against to Salmonella gallinarum
2009
Kim, H.J., Hoseo University, Asan, Republic of Korea
Streptomyces (S.) fradiae is a microbe with broad-spectrum antimicrobial activity, isolated from soil. In the present study, antibacterial effects of S. fradiaea against Salmonella (S.) gallinarum was determined. S. fradiae inhibited growing of S. gallinarum in Luria-Bertani media agar. Moreover, ingestion of S. fradiae markedly inhibited mortality of chickens experimentally infected with S. gallinarum. There is no side effect by S. fradiaeon, in safety of chickens and antibiotic material residues in chicken meat. Taken together, S. fradiae have the antibacterial effects against S. gallinarum. Therefore, we concluded that S. fradiae might be a good microbial candidate for treatment or control of fowl typhoid in chickens.
Afficher plus [+] Moins [-]Comparison of Process and cost of disposal methods for brucellosis infected bovine carcasses: burial, recycling, and incineration
2009
Yoon, H.C., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea | Yhee, J.Y., Konkuk University, Seoul, Republic of Korea | Yu, C.H., Konkuk University, Seoul, Republic of Korea | Kim, J.H., Konkuk University, Seoul, Republic of Korea | Moon, O.K., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea | Park, J.Y., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea | Nam, G.W., Konkuk University, Seoul, Republic of Korea | Sur, J.H., Konkuk University, Seoul, Republic of Korea | Rhee, H.C., Sungkyunkwan University, Seoul, Republic of Korea | Kim, T.J., Konkuk University, Seoul, Republic of Korea | Lee, S.J., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea
In korea, burial is the most common method of disposing animal carcasses culled due to brucellosis infection. However, burial has many disadvantages such as shortage of appropriate burial sites, possibile pollution of ground water supply, and negative view of the public. In this study, we have reviewed 3 legal methods for disposing bovine carcasses, which are burial, incineration, and rendering. We also described the overall process, advantages and disadvantages, and required costs for each method. About 75% of bovine brucellosis outbreak farms had less than 3 reactors, and in our study, rendering required the least amount of cost for farms with a small number of reactors (1-3 heads). Our findings suggest that the use of rendering should be encouraged for farms with bovine brucellosis and other methods considered only if rendering is inappropriate.
Afficher plus [+] Moins [-]A simulation model for evaluating serological monitoring program of Aujeszky's disease
2009
Chang, K.Y., Ministry for Food, Agriculture, Forestry and Fisheries, Gwacheon, Republic of Korea | Pak, S.I., Kangwon National University, Chuncheon, Republic of Korea | Park, C.K., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea | Lee, K.K., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea | Joo, Y.S., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea
The objective of this study was to analyze data from the planned national serological monitoring program for Aujeszky's disease (AD) using a simulation model to evaluate probable outcomes expected in the sample derived from the simulated herds at predefined within-herd prevalence and herd prevalence. Additionally, prevalence at animal- and herd-level estimated by the stochastic simulation model based on the distributions of the proportion of infected herds and test-positive animals was compared with those of data from a national serological survey in 2006, in which 106,762 fattening pigs from 5,325 herds were tested for AD using a commercial ELISA kit. A fixed value of 95% was used for test sensitivity, and the specificity was modeled with a minimum, most likely and maximum of 95, 97 and 99%, respectively. The within-herd prevalence and herd prevalence was modeled using Pert and Triang distributions, respectively with a minimum, most likely and maximum point values. In all calulations, population size of 1,000 was used due to lack of representative information. The mean number of infected herds and true test-positives was estimated to be 27 herds (median=25; 95% percentile 44) and 214 pigs (median=196; 95% percentile 423), respectively. When testing 20 pigs (mean of 2006 survey) in each herd, there was a 3.3% probability that the potential for false-positive reactions due to less than 100% specificity of the ELISA test would be detected. It was found that the model showed prevalence of 0.21% (99% percentile 0.50%) and 0.5% (99% percentile 0.99%) at animal- and herd-level, respectively. These rates were much similar to data from the 2006 survey (0.62% versus 0.83%). The overall mean herd-level sensitivity of the 2006 survey for fattening pigs was 99.9%, with only a 0.2% probability of failing to detect at least one infected herd.
Afficher plus [+] Moins [-]A case of polypoid cystitis in a dog
2009
Im, E.J., Jeju National University, Jeju, Republic of Korea | Kang, S.C., Preclinical Research Center, Chemon Inc., Yongin, Republic of Korea | Jung, J.Y., Jeju National University, Jeju, Republic of Korea | Jeon, J.N., Kang-Nam Animal Hospital, Seoul, Republic of Korea | Kim, J.H., Jeju National University, Jeju, Republic of Korea
Among benign proliferation of the urinary bladder, polypoid cystitis is a rare disease in dogs. It is characterized by epithelial proliferation, chronic inflammation in lamina propria, and development of a polypoid mass or masses without evidence of neoplasia. This report describes histopathologic features of polypoid cystitis in dog. A 10-year-old spayed female shihtzu-dog was presented with two-month history of hematuria. Abdominal ultrasonography confirmed the thickened bladder wall and calculi in both kidneys. Surgical biopsy sample was taken from the thickeded bladder mucosa for the histopathologic examination. The mass was covered with irregular hyperplastic transitional epithelium with the projection into the lumen in multifocal areas as well as many Brunn's nests in lamina propria. Many inflammatory cells such as lymphocyte, plasma cell, and macrophage and few neutrophils were occupied in lamina propria and submucosa. Proliferated fibrous tissues in lamina propria were clarified by using special staining methods. These collagens were stained blue with Masson's trichrome and red with van Gieson, but negative for alcian blue. Based on the clinical, gross, and histopathologic examinations, this case was diagnosed as polypoid cystitis in a dog. In our best knowledge, this is first report of polypoid cystitis in dog in Korea.
Afficher plus [+] Moins [-]Antibiotic resistance pattern of avian pathogenic Escherichia coli isolated from chickens
2009
Kim, M.S., Kangwon National University, Chuncheon, Republic of Korea | Kwon, H.M., Kangwon National University, Chuncheon, Republic of Korea | Sung, H.W., Kangwon National University, Chuncheon, Republic of Korea
Avian pathogenic Escherichia coli (APEC) is an important bacterial pathogen of chickens and causes colibacillosis such as airsacculitis, perihepatitis, omphalitis, peritonitis, salpingitis and pericarditis. As the transfer of antibiotic resistance from animal to humans can be possible surveillance on antibiotic resistance of APEC is very important. A total 34 APEC isolates from diseased chickens during the period from 2007 to 2009 were obtained. The susceptibility of the isolates to 13 antibiotics was determined by disc diffusion assay. Resistance to erythromycin was found in 97.1% of APEC isolated, followed by resistance to tetracycline (85.3%), doxycycline (82.3%), ampicillin (73.5%), sulfisoxazole (67.6%), enrofloxacin (67.6%), ciprofloxacin (64.7%), norfloxacin (61.7%) trimethoprim/sulfamethoxazole (52.9%), gentamycin (26.5%), amoxicillin (8.8%), colistin (5.9%), and amikacin (2.9%). The blaTEM genes were detected in 25 (100%) of the 25 ampicillin-resistant APEC isolates. Among the 29 tetracycline-resistant APEC isolates, tetA and tetB genes were detected in 18 (62.1%) and 9 (31%) isolates, respectively. Twenty six (76.5%) isolates were multiresistant to at least 6 antibiotics and seven (20.1%) isolates were multiresistant to at least 10 antibiotics. This results indicated that multiple antibiotic-resistant APEC is widespread in chicken flocks in Korea.
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