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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.
Mostrar más [+] Menos [-]Anti-mycoplasmal and anti-inflammatory effect of Origanum vulgare extract against Mycoplasma hyopneumoniae
2009
Choi, M.J., Kyungpook National University, Daegu, Republic of Korea | Hwang, M.H., Kyungpook National University, Daegu, Republic of Korea | Choi, J.Y., Kyungpook National University, Daegu, Republic of Korea | Lee, J.S., Kyungpook National University, Daegu, Republic of Korea | Park, S.C., Kyungpook National University, Daegu, Republic of Korea
In the present study, ten herbal extracts, Citirus unchiu Markovich, root and stem of Berberis koreana, Morus alba, Dendrobium moniliforme, Aster gramineus, A. scabar, Alisma canaliculatum, Fallopia japonica and Origamum (O.) vulgare were determined to examine anti-mycoplasmal activity. Among them, O. vulgare extract (OVE) showed strong anti-mycoplasmal activity and was analyzed by gas-chromatography/mass spectrometry (GC/MS). As the results, OVE was consisted of carvacrol (68.78%), o-cymene (9.80%), terpinene (7.61%) and thymol (4.03%) as main ingredients. To investigate inflammatory activity by intact pathogenic Mycoplasma hyoneumoniae (M. hyo) at 30 ㎍/mL, we examined induced transcription of proinflammatory cytokines such as cyclooxygenase-2, tumor necrosis factor-a, interleukin (IL)-1, IL-6 and inducible nitric oxide synthase in RAW 264.7 cells. With the above results, we further investigated whether OVE could reduce inflammation induced by M. hyo at minimal inhibitory concentration. The result showed that 32 ㎍/mL of OVE inhibited nitric oxide production by 60%. This study also evaluated the combination of OVE with antibacterials against M. hyo for application. Based on these results, it could be concluded that M. hyo induces inflammation in RAW 264.7 cells and OVE protects this inflammation, indicating that OVE may be useful for industrial animals.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]Relationship between the formation of Schmidt-Lantermann incisure and the localization of neurofascin in rat sciatic nerve
2009
Choi, H.Y., Konkuk University, Seoul, Republic of Korea | Cho, I.H., Jeju National University, Jeju, Republic of Korea | Lee, J.H., Konkuk University, Seoul, Republic of Korea | Nahm, S.S., Konkuk University, Seoul, Republic of Korea | Chang, B.J., Konkuk University, Seoul, Republic of Korea
Neurofascin, one of the members of L1CAM, has been known to have some important roles during the development of nerve fibers. In order to investigate the role of neurofascin associated with the formation of Schmidt-Lantermann incisure in the sciatic nerve, the localization of neurofascin was studied with electron microscopy, immuno-fluorescence and immuno-electron microscopy. In the electron microscopy, the first formation of Schmidt-Lantermann incisure was checked at postnatal day 6 and the complete form of incisures traversing the whole myelin sheath began to be observed at postnatal day 8. In the immunofluorescence, neurofascin immunoreactive Schmidt-Lantermann incisures were first checked at postnatal day 6 and dramatically increased with aging by postnatal day 56. In the immunoelectron microscopy, neurofascin immunoreactive gold particles at the incisure forming sites were first observed at postnatal day 6 and the number of gold particles was increased as the animal was getting old by postnatal day 56. According to the present study, neurofascin is likely to have some relationships with Schmidt-Lantermann incisure formation.
Mostrar más [+] Menos [-]Effect of PCB118 on expression of COX-2 and cPLA2 in rat testes
2009
Han, D.Y., Gyeongsang National University, Jinju, Republic of Korea | Park, K.I., Gyeongsang National University, Jinju, Republic of Korea | Park, H.S., Gyeongsang National University, Jinju, Republic of Korea | Kang, S.R., Gyeongsang National University, Jinju, Republic of Korea | Cho, J.H., Gyeongsang National University, Jinju, Republic of Korea | Lee, H.J., Gyeongsang National University, Jinju, Republic of Korea | Kim, E.H., International University of Korea, Jinju, Republic of Korea | Kim, G.S., Gyeongsang National University, Jinju, Republic of Korea
Polychlorinated biphenyls (PCBs) are synthetic organic compounds with two benzene rings and well known environmental pollutants. This study examined the effect of persistent exposure to 2,3',4,4',5-pentachlorobiphenyl (PCB118) on the proinflammatory and proapoptotic factors in male rats. Male Sprague Dawley rats were administered weekly intraperitoneal injections of either PCB118 (20 mg/kg) dissolved in corn oil or corn oil alone. One week after 2 and 5 administrations, the rats were sacrificed by a pentobarbital injection. The effect of PCB118 on the expression of cyclooxygenase 2 (COX-2), cytosolic phospholipase A2 (cPLA2), peroxisome proliferator-activated receptor gamma, Bcl and Bcl-2-associated X protein (BAX) was investigated. The level of COX-2 and cPLA2 expression was higher in the PCB118-treated rats than the control. These results suggest that PCB118 has a proinflammatory effect in rats.
Mostrar más [+] Menos [-]Hypoparathyroidism in a diabetic dog
2009
Lee, H.J., Chungnam National University, Daejeon, Republic of Korea | Lim, S.J., Chungnam National University, Daejeon, Republic of Korea | Lee, S.H., Chungnam National University, Daejeon, Republic of Korea | Song, E.S., Chungnam National University, Daejeon, Republic of Korea | Song, K.H., Chungnam National University, Daejeon, Republic of Korea
A miniature schnauzer (8 years old, male castrated), diagnosed as diabetes mellitus 6 months ahead, were referred to the Veterinary Medical Teaching Hospital of our University with hindlimb stiffness, facial rubbing and tetany. Serum chemistry showed severe hypocalcemia, hypomagnesemia, and measured iPTH (intact pharathyroid hormone) concentration was low (less than 3.0 pmol/L). Consistent rate injection of calcium gluconate (282 mg/kg over 30 min) resulted in prompt relief of the tetany. Then typical treatment for hypoparathyroidism (calcium gluconate and dihydrotachysterol per os) with magnesium administration could control the neuromuscular signs. Diabetes mellitus is being controlled by insulin therapy and prescription diet. Hypomagnesemia in diabetic dog may be induced hypoparathyrodism.
Mostrar más [+] Menos [-]Assessing the economics of animal trypanosomosis in Africa-history and current perspectives Texto completo
2009
Shaw, A.P.M.(A P Consultants)
Finding appropriate ways of dealing with the problem of tsetse and trypanosomosis will be an important component of efforts to alleviate poverty in Africa. This article reviews the history of economic analyses of the problem, starting with the use of cost to guide choice of technique for tsetse control in the 1950s, followed by work in the 1970s and 1980s linking these to the impact of the disease on livestock productivity, and in the 1990s to its wider impact. In the current situation, with limited resources and a range of techniques for controlling or eliminating tsetse, the cost implications of choosing one technique or another are important and a recent study reviewed these costs. A novel approach to assessing the potential benefits from removing trypanosomosis by creating 'money maps' showed that high losses from animal trypanosomosis currently occur in areas with high cattle population densities on the margins of the tsetse distribution and where animal traction is an important component of farming systems. Given the importance of the decisions to be made in the next decade, when prioritising and choosing techniques for dealing with tsetse and trypanosomosis, more work needs to be done underpinning such mapping exercises and estimating the true cost and likely impact of planned interventions.
Mostrar más [+] Menos [-]Tsetse and trypanosomosis in Africa: The challenges, the opportunities Texto completo
2009
Ilemobade, A.A.(Upline Resources Foundation)
Tsetse-fly and the disease it transmits, trypanosomosis, remain an enormous disease challenge in the 37 countries of sub-Saharan Africa where the impact continues to be manifest in disease burden, increased level of poverty and decreased agricultural productivity. The impact also extends over an estimated 10 million km² (a third of the African continent) of land area, a third of which contains some well-watered part of the continent, thus denying humans and livestock of potentially rich arable and pastureland. The disease is a threat to an estimated 50 million people and 48 million cattle with estimated annual losses in cattle production alone of 1-1.2 billion US$. These losses are due to stock mortality and depressed productivity, which may be of meat, milk, reproduction or traction. Beyond its direct effects on humans and livestock is its impact on African agriculture and the livelihood of the rural population in the affected countries: the fly and the disease influence where people decide to live, how they manage their livestock, and the intensity and the mix of crop agriculture. The combined effects result in changes in land use and environment which may, in turn, affect human welfare and increase the vulnerability of agricultural activity. Trypanosomosis is, therefore, both a public health and an agricultural development constraint. The challenges that the elimination or control of tsetse fly and trypanosomosis pose as well as the opportunities to develop appropriate intervention technologies are discussed in this presentation.
Mostrar más [+] Menos [-]Persistence mechanisms in tick-borne diseases Texto completo
2009
Barbet, A.F.(University of Florida College of Veterinary Medicine Department of Infectious Diseases & Pathology)
The use of new, highly sensitive diagnostic methods has revealed persistent infections to be a common feature of different tick-borne diseases, such as babesiosis, anaplasmosis and heartwater. Antigenic variation can contribute to disease persistence through the continual elaboration of new surface structures, and we know in several instances how this is achieved. Known or suspected mechanisms of persistence in babesial parasites include cytoadhesion and rapid variation of the adhesive ligand in Babesia bovis and genetic diversity in several merozoite stage proteins of different Babesia spp. In Anaplasma, extensive variation in the pfam01617 gene family accompanies cycling of organism levels in chronic infection. One result from the pioneering research at Onderstepoort is the definition of a related polymorphic gene family that is likely involved in immunity against heartwater disease. We are beginning to understand the sizes of the antigenic repertoires and full definition is close, with the possibility of applying simultaneous high-throughput sequencing to the order of 1 000 small genomes. We also, for the first time, can consider modifying these genomes and looking at effects on persistence and virulence. However, important biological questions remain unanswered; for example, why we are seeing a new emerging Anaplasma infection of humans and is infection of endothelial cells by Anaplasma significant to persistence in vivo.
Mostrar más [+] Menos [-]Sir Arnold Theiler and the discovery of anaplasmosis: A centennial perspective Texto completo
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.
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