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Inducible nitric oxide synthase is involved in neuronal death induced by trimethyltin in the rat hippocampus
2011
Jang, S.W., Jeju National University, Jeju, Republic of Korea | Choi, S.Y., Jeju National University, Jeju, Republic of Korea | Park, C.N., Jeju National University, Jeju, Republic of Korea | Ahn, M.J., Jeju National University, Jeju, Republic of Korea | Shin, T.K., Jeju National University, Jeju, Republic of Korea | Kim, S.J., Kyungpook National University, Daegu, Republic of Korea
Trimethyltin chloride (TMT) has been used as a neurotoxin for inducing brain dysfunction and neuronal death. Neuronal death in the hippocampus by TMT may generate excessive nitric oxide, but there are few studies about nitric oxide synthase enzyme involved in the synthesis of nitric oxide. The purpose of present study is to analyze the TMT toxicity in each region of rat hippocampus. To evaluate the involvement of nitric oxide, we analyzed the effects of aminoguanidine known as a selective inhibitor for inducible nitric oxide synthase on behavioral changes and the hippocampus of rat by TMT toxicity. 6-week-old male Sprague-Dawley rats were administered with a single dose of TMT (8 mg/kg b.w., i.p.) and the control group was similarly administered with distilled water. TMT + aminoguanidine-treated groups were administered with aminoguanidine (10 mg/kg or 100 mg/kg b.w., i.p.) for 3 days prior to TMT injection. The rats were sacrificed 2 days after TMT administration. In the TMT-treated group, a number of cell losses were seen in CA1, CA3 and the dentate gyrus. In the TMT + aminoguanidine-treated group, neuronal death was seen in CA1 and CA3, but reduced in the dentate gyrus compared to the TMT-treated group. Western blot analysis showed that cleaved caspase-3 expression was increased in the TMT-treated group compared to the control group. However, the expression significantly declined in the TMT + aminoguanidine-treated group. The present findings suggest that inducible nitric oxide synthase is involved in neuronal death induced by TMT.
Показать больше [+] Меньше [-]Development of an attenuated vaccine strain from a korean respiratory type infectious bronchitis virus
2011
Choi, K.S., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea | Jeon, W.J., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea | Lee, E.K., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea | Kye, S.J., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea | Park, M.J., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea | Kwon, J.H., Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Republic of Korea
An attenuated vaccine strain AVR1/08 of Korean respiratory type of infectious bronchitis virus (IBV) was developed by 89th passages of IBV D85/06 strain in chicken eggs. The AVR1/08 strain had higher virus titer at least 20 times (10∨1.3) than the parent virus D85/06 by egg inoculation method. The AVR1/08 strain had a single point mutation (S to Y) at position 56 of spike protein of IBV compared to parent virus IBV D85/06 strain. The mutation was observed consistently at viruses after 47th passage in chicken eggs. The AVR1/08 strain showed no virulence even after 6 passages in chickens and all chickens inoculated induced anti-IBV antibody 14 days after vaccination. The AVR1/08 strain had broad protective efficacy against QX type Korean nephropathogenic virus (Q43/06 strain), KM91 type Korean nephropathogenic virus (KM91 strain) and Korean respiratory virus (D85/06 strain). In contrast, Massachusetts (Mass) type attenuated vaccine strain H120 showed protection of 37.5 to 50% against these three viruses. Our results indicate that the AVR1/08 strain has potential as an attenuated vaccine effective in controlling IBVs circulating in Korea.
Показать больше [+] Меньше [-]Glatiramer acetate inhibits the activation of NFκB in the CNS of experimental autoimmune encephalomyelitis
2011
Hwang, I.S., Jeju National University, Jeju, Republic of Korea | Ha, D.B., Jeju National University, Jeju, Republic of Korea | Kim, D.S., Jeju National University, Jeju, Republic of Korea | Joo, H.J., Jeju National University, Jeju, Republic of Korea | Jee, Y.H., Jeju National University, Jeju, Republic of Korea
Glatiramer acetate (GA; Copaxone) has been shown to be effective in preventing and suppressing experimental autoimmune encephalomyelitis (EAE), the animal model of multiple sclerosis (MS). It has been recently shown that GA-reactive T cells migrate through the blood-brain barrier, accumulate in the central nervous system (CNS), secrete antiinflammatory cytokines and suppress production of proinflammatory cytokines of EAE and MS. Development of EAE requires coordinated expression of a number of genes involved in the activation and effector functions of inflammatory cells. Activation of inflammatory cells is regulated at the transcriptional level by several families of transcription factors. One of these is the nuclear factor kappa B (NFκB) family which is present in a variety of cell types and involved in the activation of immune-relative genes during inflammatory process. Since it is highly activated at site of inflammation, NFκB activation is also implicated in the pathogenesis of EAE. In this study, we examined whether the inhibition of NFκB activation induced by GA can have suppressive therapeutic effects in EAE mice. We observed the expression of NFκB and phospho-IκB proteins increased in GA-treated EAE mice compared to EAE control groups. The immunoreactivity in inflammatory cells and glial cells of NFκB and phospho-IκB significantly decreased at the GA-treated EAE mice. These results suggest that treatment of GA in EAE inhibits the activation of NFκB and phophorylation of IκB in the CNS. Subsequently, the inhibition of NFκB activation and IκB phosphorylation leads to the anti-inflammatory effects thereby to reduce the progression and severity of EAE.
Показать больше [+] Меньше [-]Kinetics of HMGB1 level changes in a canine endotoxemia model
2011
Yu, D.H., University of Missouri, Columbia, MO, USA | Park, J.H., Chonbuk National University, Jeonju, Republic of Korea
In this study, we investigated the kinetics of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and high mobility group box 1 (HMGB1) concentrations in a 48-h model of canine endotoxemia by lipopolysaccharide (LPS) injection. Four healthy beagles were slowly administered 1 mg/kg of LPS diluted in normal saline, while two others were administered normal saline as controls. Blood collection was performed at 0 h (baseline), 1 h and 3 h (for TNF-α), 6 h, 12 h, 24 h and 48 h of the experiment, and cytokine levels were determined using the sandwich ELISA method. Early increments of TNF-α and IL-6 were observed (less than 3 h), but HMGB1 levels increased the most at 12 h of the experiment and gradually decreased until 48 h. During the whole experiment, IL-6 and HMGB1 were sustained over 12 h of LPS injection, whereas TNF-α decreased within 6 h of LPS injection. Taken together, canine HMGB1 levels increase relatively late (less than 12 h) and sustained longer than TNF-α and IL-6 in response to endotoxin. This is the first study to evaluate canine HMGB1 cytokine from endotoxemia in dogs.
Показать больше [+] Меньше [-]Protective effect of ethyl acetate extract of Ishige okamurae against carbon tetrachloride-induced acute liver injury in rats
2011
Kang, S.H., Jeju National University, Jeju, Republic of Korea | Yang, W.J., Jeju National University, Jeju, Republic of Korea | Oh, H.S., Jeju National University, Jeju, Republic of Korea | Bae, Y.J., Jeju National University, Jeju, Republic of Korea | Ahn, M.J., Jeju National University, Jeju, Republic of Korea | Kang, M.C., Jeju Technopark, Jeju, Republic of Korea | Ko, R.K., Jeju Technopark, Jeju, Republic of Korea | Kim, G.O., Jeju Technopark, Jeju, Republic of Korea | Lee, J.H., Samsung Changwon Hospital, School of Medicine, Sungkyunkwan University, Changwon, Republic of Korea | Hyun, J.W., Jeju National University, Jeju, Republic of Korea | Moon, C.J., Chonnam National University, Gwangju, Republic of Korea | Shin, T.K., Jeju National University, Jeju, Republic of Korea
Several compounds and extracts isolated from a brown alga, Ishige (I.) okamurae, exhibit anti-oxidant and anti-inflammatory effects. The present study investigated whether the ethyl acetate (EtOAc) fraction of I. okamurae (EFIO) could ameliorate carbon tetrachloride (CCl₄)-induced hepatotoxicity in rats. Sprague-Dawley rats were intraperitoneally (i.p.) administered with EFIO at 10 or 50 mg/kg per day for 2 consecutive days before CCl₄ injection (3.3 mL/kg, i.p.). Twenty four hours later, the rats were anesthesized with diethyl ether and dissected. Pretreatment with EFIO significantly reduced the increased serum levels of alanine aminotransferase and aspartate aminotransferase in CCl₄-treated rats. Pretreatment with EFIO also significantly inhibited the reduced activities of superoxide dismutase and catalase in the CCl₄-injured liver. Histopathological evaluations showed that hemorrhage, hepatocyte necrosis, inflammatory cell infiltration, and fatty degeneration induced by CCl₄ treatment were ameliorated by the administration of EFIO. Additionally, liver immunohistochemical analyses revealed the marked reduction in ED1-positive monocyte-like macrophages in EFIO-pretreated rats given CCl₄. These results suggest that EFIO ameliorates CCl₄-induced liver injury, possibly through the inhibition of oxidative stress.
Показать больше [+] Меньше [-]Genetic characterization of methicillin-resistant Staphylococcus aureus from humans and animals within the community
2011
Cho, J.K., Metropolitan Health and Environmental Research Institute, Daegu, Republic of Korea | Kim, J.H., Gangwondo Veterinary Serivice Laboratory, Pyeongchang, Republic of Korea | Sung, M.S., Gyeongbuk Veterinary Serivice Laboratory, Daegu, Republic of Korea | Kim, K.S., Kyungpook National University, Daegu, Republic of Korea
Methicillin-resistant Staphylococcus (S.) aureus (MRSA) is one of the most important nosocomial pathogens worldwide and the emergence of this strain has become a major clinical problem. In this study, we investigated the prevalence of MRSA and their genetic characteristics in 69 S. aureus isolated from humans and animals. In human isolates, higher antimicrobial resistance rates were observed against penicillin (80.6%), followed by erythromycin (11.9%) and tetracycline (9.0%). All of them were susceptible to clindamycin, enrofloxacin, novobiocin, pirlimycin, trimethoprim/sulfamethoxazole and vancomycin. The resistance patterns in animal isolates were similar to those of human isolates. Two (2.9%) MRSA strains were isolated from human (n = 1) and animal (n = 1), and these isolates were confirmed as carrying the mecA gene. One isolate originating from human was resistant to 7 drugs and the other isolate derived from animal was resistant to 11 drugs. Staphylococcal cassette chromosome mec (SCCmec) variant IIIB was identified in animal isolate but SCCmec type of an isolate from human was not exactly determined. Two MRSA isolates showed unrelated PFGE pattern between them. Our results indicated although the frequency of MRSA isolates from humans and animals was low, a continuous surveillance and monitoring should be called for to prevent the contamination and spread of MRSA in the community. To our knowledge, this is the first time that SCCmec type variant IIIB was detected from animals in Korea.
Показать больше [+] Меньше [-]Immuno-enhancing Effects of Lactobacillus salivarius JWS 58 and Lactobacillus plantarum JWS 1354 isolated from duck
2011
Choi, H.J., Chungbuk National University, Cheongju, Republic of Korea | Kim, J.Y., Chungbuk National University, Cheongju, Republic of Korea | Shin, M.S., Chungbuk National University, Cheongju, Republic of Korea | Lee, S.M., Chonbuk National University, Iksan, Republic of Korea | Lee, W.K., Chungbuk National University, Cheongju, Republic of Korea
Lactobacillus salivarius JWS 58 (JWS 58) and Lactobacillus plantarum JWS 1354 (JWS 1354) are isolated from duck intestine and have ability to produce bacteriocin. The objective of this study was to evaluate the immunomodulatory effects of JWS 58 and JWS 1354. The nitric oxide (NO) and cytokines (IL-1β and TNF-α) were measured in C57BL/6 mouse peritoneal macrophages to determine immune enhancing effects of JWS 58 and JWS 1354. A Listeria (L.) monocytogenes challenge mice model was used to evaluate immune enhancement ability of JWS 58 and JWS 1354 in vivo. The results showed that JWS 58 and JWS 1354 increased the production of NO or cytokines by peritoneal macrophages and that oral administration of viable probiotic strains in mice elicited the immuno-modulatory effect upon L. monocytogenes challenge. JWS 1354 showed stronger immune enhancing effects than JWS 58. Collectively, this study demonstrated that Lactobacillus strain JWS 58 and JWS 1354 possess immune enhancing effect. Furthermore, two stains are expected to use feed supplement to prevent diseases by pathogenic bacteria through releasing bacteriocin and enhancing host immune responses in animal.
Показать больше [+] Меньше [-]Rate of return to race after arthroscopic surgeries in Thoroughbred racehorses (2005~2010)
2011
Yang, J.H., Jeju Race Park, Korea Racing Authority, Jeju, Republic of Korea | Lim, Y.K., Jeju National University, Jeju, Republic of Korea
The racehorses that under arthroscopic surgery due to be injured his limbs were studied during exercise or training at Busan Race Park from 2005 to 2010. Rate of arthroscopic surgical treatments was 1.4% (63/4,642). Affected bones were radius, radial carpal bone, third carpal bone, proximal phalanx, third metacarpal bone, femur, tibia, proximal sesamoid bone and intermediate carpal bone. The lesions were fracture, chip fracture, slap fracture, osteochonrosis, and osteochondrotitis dissencans. Number of patients under arthroscopic surgery were 63. Success horses of returned to racetrack or tried to return to racetrack were 58, and 5 horses were in training or resting at the time of publication. Success horses of returned to their previous use in the patients were 49 horses (84.4%) and no returned to the racetrack were 9 horses (15.6%) in 58 horses.
Показать больше [+] Меньше [-]Awareness effects by aquapuncture with dexamethasone in tiletamine/zolazepam anesthetized dogs
2011
Park, H.J., Chungnam National University, Daejeon, Republic of Korea | Song, K.H., Chungnam National University, Daejeon, Republic of Korea | Kim, D.H., Chungnam National University, Daejeon, Republic of Korea
Awareness effect of aquapuncture with dexamethasone on GV-26 was studied in tiletamine/zolazapam anesthetized six healthy crossbred dogs using a randomized cross-over experimental study design. After anesthesia by tiletamine/zolazapam, 0.1 mg dexamethasone was injected on GV-26 at 20 min in the experimental group. For the control group, 0.1 mg dexamethasone was injected on the quadriceps femoralis. A significant difference was evident in the sedation score between groups at 60 and 90 min (p less than 0.05). A significant difference was also evident in the analgesia score at 50 and 60 min (p less than 0.05). At 90 min, all dogs in the experimental group responded strongly to pain (p less than 0.01). Head up time, sternal recumbent time, standing time, and walking time was shorter in the experimental group, but the difference from the control group was statistically significant only for head up time and walking time (p less than 0.05). GV-26 acupuncture with dexamethasone is useful for awareness effects after anesthesia.
Показать больше [+] Меньше [-]Pattern alopecia in a miniature pinscher dog
2011
Kang, J.I., Chungnam National University, Daejeon, Republic of Korea | Lee, W.H., Chungnam National University, Daejeon, Republic of Korea | Park, J.H., Chungnam National University, Daejeon, Republic of Korea | Oh, T.H., Kyungpook National University, Daegu, Republic of Korea | Cho, S.W., Chungnam National University, Daejeon, Republic of Korea | Park, S.J., Chungnam National University, Daejeon, Republic of Korea
A dog (5.6 kg, 4-year-old, castrated male, Miniature pinscher) with diffuse symmetric alopecia on the chest and excessive scales was referred to Veterinary Medical Teaching Hospital of Chungnam National University, Korea. On physical examination, diffuse alopecia on ventral aspect of the neck and caudomedial thighs, and severe scales were presented. Dermatologic tests of lesions revealed bacterial infections. Histopathologically, atrophy of hair bulb was observed in the severely alopecic lesion of caudomedial thighs. ACTH stimulation test was performed to differentiate the endocrine disorder related to generalized alopecia. The pre-ACTH serum testosterone and progesterone concentrations were above normal ranges and the post-ACTH serum testosterone concentration was high. The pre- and post-ACTH serum estradiol and cortisol concentrations were within normal ranges. Canine pattern alopecia was diagnosed based on history, physical examination, hormonal assay and dermatohistopathologic examination. After 3 months of melatonin administration, multifocal alopecia on the trunk was improved and general hair regrowth was identified.
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