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941.
Cho A 《Science (New York, N.Y.)》2012,335(6074):1287-1288
942.
In 1995, a serious necrotic disease appeared in Asian pear trees in the orchards of Chuncheon, South Korea. Large numbers of bacterial samples were collected, and the causative microorganism was identified as a novel pathogen, Erwinia pyrifoliae. Among the samples, four bacterial isolates with atypical characteristics were further analyzed through biochemical tests and 16S rRNA gene sequence analysis. By phenotypic and genetic analysis these isolates were identified as E. rhapontici. Phylogenetic analysis using 16S rRNA sequence data revealed that E. rhapontici forms a discrete clade with high bootstrap value close to the E. amylovora group. Pathogenicity tests on leaves of tobacco plants (Nicotiana tabacum) elicited hypersensitivity responses, but artificial inoculations on immature fruits and shoots of Asian pear (Pyrus pyrifolia) did not show any necrotic symptoms. The developed primers showed no cross reactivity when tested against other phytopathogens and were able to detect E. rhapontici from mixed culture and in planta. 相似文献
943.
To overcome the limitations of serological diagnosis, including false positive reactions caused by other pathogens, specific antigens for diagnosis of brucellosis other than LPS have been required. The present study was conducted to separate and identify immuno-dominant insoluble proteins of Brucella abortus against the antisera of cattle infected with B. abortus, or/and Yersinia enterocolitica, or the sera of non-infected cattle. After separating insoluble proteins of B. abortus by two dimensional electrophoresis (2-DE), their immuno-reactivity was determined by western blotting. A portion of the immunogenic spots against the positive antisera of B. abortus that have the potential for use as specific antigens were identified by MS/MS analysis. Overall, 18 immunogenic insoluble proteins of B. abortus 1119-3 showed immuno-reactivity against only the positive antisera of B. abortus, but failed to have immunogenicity toward both the positive sera of Y. enterocolitica and the negative sera of B. abortus. Identification of these proteins revealed the following: F0F1 ATP synthase subunit β, solute-binding family 5 protein, 28 kDa OMP, Leu/Ile/Val-binding family protein, Histidinol dehyddrogenase, Hypothetical protein, Twin-arginine translocation pathway signal sequence domain-containing protein, Dihydroorotase, Serine protease family protein, β-hydroxyacyl-(acyl-carrier-protein) dehydratase FabA, Short-chain dehydrogenase-/reductase carbonic anhydrase, Orinithine carbamoyltransferase, Leucyl aminopeptidase, Cold shock DNA-binding domain-containing protein, Cu/Zn superoxide dismutase, and Methionine aminopeptidase. The 18 immunogenic proteins separated in the present study can be considered candidate antigens to minimize cross reaction in the diagnosis of brucellosis and useful sources for Brucella vaccine development. 相似文献
944.
The LEC rat is reported to exhibit hypersensitivity to X-irradiation, deficiency in DNA double-strand break repair, and radio-resistant DNA synthesis. This character of the LEC rat has been thought to be due to abnormal G1 arrest in cells after X-irradiation. In this report, we re-investigated the effect of X-irradiation on the cell cycle in primary-cultured fibroblasts. Primary-cultured fibroblasts derived from LEC and BN rats were exposed to 4 Gy of X-ray and their cell cycle analysis was performed with a flow cytometer. Fibroblasts derived from both rats showed normal response of the cell cycle, indicating the arrest at both G1--and G2/M-phase and no difference in the cell cycle population between fibroblasts derived from both rats. In contrast, when the same analysis was performed using the cell line, L7 and W8, which had been established from the lung fibroblasts of LEC and control WKAH rats, respectively, by immortalizing with SV40 T-antigen, L7 cells but not W8 cells showed impaired G1 arrest and abnormal cell cycle. These results suggest that fibroblasts derived from LEC rats possess the normal cell cycle response after X-irradiation, if they are kept naive as not immortalized with SV40 T-antigen. 相似文献
945.
Yoon HA Eo SK Aleyas AG Cha SY Lee JH Chae JS Jang HK Cho EG Song HJ 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(2):143-148
The prevalence and quantity of latent pseudorabies virus (PrV) in nervous tissues of pigs exposed to field strain in Korea was investigated by nested and real-time PCR. Nervous tissues including trigeminal ganglion (TG), olfactory bulb (OB), and brain stem (BS) were collected from 94 seropositive pigs. PrV latent infection in nervous tissues was initially investigated by nested PCR targeting three glycoprotein genes (gB, gE, and gG). Based on the obtained result, latent infection was detected in 95.7% of screened animals. Furthermore, it was revealed that the examined tissues harbored different copy numbers of latent PrV genome ranging from <10(2.0) to 10(7.1) copies per microgram of genomic DNA in real-time PCR analysis. These results show that under normal conditions, levels of latent PrV in the nervous tissues of pigs can vary across a wide range. Therefore, the data presented here provides information regarding control of the endemic state of PrV in Korea. 相似文献
946.
Kim TJ Cho HS Park NY Lee JI 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2006,53(2):87-90
A protein chip based on surface plasmon resonance (SPR) was developed for measuring the Mycoplasma hyopneumoniae antibody titres using a recombinant 30-kDa fragment of P97 adhesin as an antigen. The diagnostic potential of this SPR assay, for detecting the antibody titres to the M. hyopneumoniae 30-kDa protein, was compared with that of conventional ELISA using 70 pig serum samples taken from six pig farms. The SPR assay was found to be highly specific and sensitive. Moreover, there was a strong positive correlation between the SPR and ELISA titres (n = 70, r = 0.898, P < 0.01). Therefore, this recombinant 30-kDa protein can be used as an antigen for serological studies, and the SPR, which is a label-free method, is expected to be a valuable and reproducible tool in the serodiagnosis of M. hyopneumoniae infection. 相似文献
947.
Su-Jin Lim Dae-jin Min Sohee Kim Jihye Lee Eun-Soo Lee Hyuk Kim Sung-Yoen Cho Heung-Soo Beak Chang-Seok Lee Sang-Jip Nam Jaeyoung Ko 《Marine drugs》2021,19(11)
An ubiquinone derivative, pseudoalteromone A (1), has been isolated from two marine-derived Pseudoalteromonas spp., APmarine002 and ROA-050, and its anti-melanogenesis activity was investigated. The anti-melanogenic capacity of pseudoalteromone A was demonstrated by assessing the intracellular and extracellular melanin content and cellular tyrosinase activity in the B16 cell line, Melan-a mouse melanocyte cell line, and MNT-1 human malignant melanoma cell line. Treatment with pseudoalteromone A (40 μg/mL) for 72 h reduced α-melanocyte-stimulating hormone (α-MSH)-induced intracellular melanin production by up to 44.68% in B16 cells and 38.24% in MNT-1 cells. Notably, pseudoalteromone A induced a concentration-dependent reduction in cellular tyrosinase activity in B16 cell, and Western blot analyses showed that this inhibitory activity was associated with a significant decrease in protein levels of tyrosinase and tyrosinase-related protein 1 (Tyrp-1), suggesting that pseudoalteromone A exerts its anti-melanogenesis activity through effects on melanogenic genes. We further evaluated the skin-whitening effect of pseudoalteromone A in the three-dimensional (3D) pigmented-epidermis model, MelanoDerm, and visualized the 3D distribution of melanin by two-photon excited fluorescence imaging in this human skin equivalent. Collectively, our findings suggest that pseudoalteromone A inhibits tyrosinase activity and expression and that this accounts for its anti-melanogenic effects in melanocytes. 相似文献
948.
Ahmad Yar Qamar Xun Fang Seonggyu Bang Sang Tae Shin Jongki Cho 《Reproduction in domestic animals》2020,55(9):1163-1171
Astaxanthin is a member of the carotenoid family well known for its anti-cancer, anti-diabetic, anti-inflammatory and antioxidant nature. This study was designed to investigate the effects of astaxanthin supplementation of the extender (buffer 2) on post-thaw dog semen quality. Semen from four healthy dogs was collected by digital manipulation twice a week. The ejaculates were pooled, washed, divided into four equal aliquots, diluted with the extender supplemented with different concentrations of astaxanthin (0, 0.5, 1 and 2 µM) and cryopreserved. The results showed that 1 µM astaxanthin was the optimum concentration that led to significantly higher (p < .05) post-thaw motility, kinematic parameters and viability than the other groups. In comparison with the control group, sperm samples supplemented with 1 µM astaxanthin showed significantly higher (p < .05) sperm counts with intact membranes (55.7 ± 0.6% vs. 51.3 ± 0.9%), intact acrosome (58.4 ± 0.7% vs. 53.5 ± 0.6%), active mitochondria (54.9 ± 0.5% vs. 42.6 ± 0.6%) and normal chromatin (67.6 ± 0.9% vs. 61.7 ± 0.6%). Furthermore, astaxanthin-supplemented samples showed significantly lower expression levels (p < .05) of pro-apoptotic (BAX), oxidative induced DNA damage repair (OGG1), oxidative stress-related (ROMO1) genes and higher expression levels of anti-apoptotic (BCL2), and sperm acrosome-associated (SPACA3) genes compared to the control. Thus, supplementation of 1 µM astaxanthin in semen extender results in improved freeze-thaw sperm quality of the dog. 相似文献
949.
Byung‐Joon Seung Seung‐Hee Cho Soo‐Hyeon Kim Min‐Kyung Bae Ha‐Young Lim Jung‐Hyang Sur 《Veterinary and comparative oncology》2021,19(1):132-139
Cutaneous mast cell tumours (MCTs) are the most frequent malignant skin tumours in dogs. Mutations in the c‐KIT proto‐oncogene are correlated with the pathogenesis and aggressiveness of MCTs. To date, studies have focused on c‐KIT mutations and KIT protein localization, with a general lack of mRNA‐level analyses. In this study, c‐KIT mRNA expression was investigated in canine MCTs by RNA in situ hybridization (RNA‐ISH). Furthermore, we evaluated associations between c‐KIT mRNA expression and the histological grade, KIT immunohistochemical staining pattern and other clinicopathological parameters. c‐KIT mRNA expression was observed in all MCT samples, appearing as clusters of dots in the cytoplasm of neoplastic cells. A significant correlation was detected between c‐KIT mRNA expression (quantified according to the H‐score and the percentage of positive cells) and the histological grade (determined using two‐and three‐tier grading systems; P < .05). We also found a significant positive correlation (all P < .05) between c‐KIT mRNA expression and the proliferation indices (mitotic index, Ki‐67, and Ag67). However, no significant associations with c‐KIT expression from RNA‐ISH were found with respect to different KIT staining patterns. Overall, these results demonstrate that c‐KIT mRNA expression might be an additional tool for measuring the c‐KIT status in canine cutaneous MCTs and could serve as a potential prognostic factor. Further studies should evaluate the prognostic significance of c‐KIT mRNA expression in a large and uniform cohort of canine MCTs. 相似文献
950.
Lee YJ Kim HJ Park CK Kim KS Bae DH Kang MS Cho JK Kim AR Kim JW Kim BH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(4):399-404
The purpose of this study was to investigate the biological and genetic characterization of persistent Salmonella isolates in an integrated broiler chicken operation, in an attempt to elucidate the source of contamination. From the breeder farm, the hatchery, the broiler farm and the chicken slaughter house of an integrated broiler chicken operation, a total of 6 serotypes were observed. Although S. Heidelberg was not detected in the broiler farm, it was consistently found in the breeder farm, the hatchery and the chicken slaughter house. Also, S. Enteritidis and S. Senftenberg were found in the hatchery and the chicken slaughter house, and the hatchery and the broiler farm, respectively. S. Gallinarum and S. Blockley were found only in the broiler farm, and S. Virchow was only recovered in the chicken slaughter house. Isolated S. Heidelberg, S. Enteritidis and S. Senftenberg strains were divided into 3, 5 and 7 types, respectively, on the basis of all properties. Especially, S. Senftenberg isolates, divided into four types by their antimicrobial resistance patterns, were all obviously the XbaI PFGE pattern. Also, four S. Enteritidis isolates resistant to nalidixic acid showed a difference in phage type and PFGE pattern. Such a different pattern was shown despite Salmonella isolates originating from an integrated broiler operation, suggesting that further epidemiological studies on many integrated chicken companies in Korea are needed. 相似文献