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261.
Outbreaks of koi herpesvirus (KHV) infection in carp are still a serious problem worldwide. KHV is closely related to other two cyprinid herpesviruses, pox herpesvirus (CHV) and haematopoietic necrosis herpesvirus (CyHV-2) in goldfish. In this study, two major KHV antigenic proteins (ORF62 and ORF68) were identified by immunoscreening using a KHV-specific polyclonal antibody, and then monoclonal antibodies were generated for immunodiagnostic studies. After screening hybridoma cells, one mAb against ORF68 (mAb-7C6) was obtained but no mAbs against ORF62. mAb-7C6 specifically reacted with a lysate of KHV-infected koi fin cells (KF-1 cells) but not with lysates of CHV- or CyHV-2-infected KF-1 cells in an immuno-blotting analysis. Similar results were shown in the following tests: (1) a indirect fluorescent antibody test using infected KF-1 cells and (2) an immunohistochemical investigation by fast red stain (infected liver) or FITC detection (infected spleen). These results suggested that mAb-7C6 specifically reacts with KHV ORF68 protein.  相似文献   
262.
In the present study, we have surveyed the presence of a bovine Theileria protozoan, Theileria orientalis, in Mongolian cattle and engorging tick populations from selected provinces and districts in Mongolia. The percentages of infection in the cattle and ticks ranged from 8.8 to 66.6 and from 3.7 to 73.3, respectively, on a per district basis. The genetic diversity of T. orientalis isolates was also studied, based on the protozoan gene encoding a major piroplasm surface protein (MPSP). At least five genotypes (types 1, 3, 5, 7, and N-3) of T. orientalis were found to be circulating among the Mongolian cattle and tick populations. In particular, types 3 and N-3 were common in most of the districts examined, while a strong geographical relationship among the genotypes was not detected in the present study. This is the first epidemiological report describing the presence of T. orientalis infection in Mongolian cattle.  相似文献   
263.
Theileria orientalis is a benign protozoan species that is widely distributed in Japan, yet sometimes causes serious economic losses in the livestock industry. In this study, we conducted a molecular survey based on genes encoding the major piroplasm surface protein (MPSP) and p23 for T. orientalis detected in cattle grazing in southern areas of Japan, consisting of 2 farms in Kumamoto prefecture (Aso and Kuma districts) and 3 farms in Okinawa prefecture (Ishigaki, Iriomote, and Yonaguni Islands). High prevalence rates of T. orientalis infection were shown in all the cattle populations using the diagnostic MPSP- and p23-PCR assays. Phylogenetic analyses revealed 4 MPSP genotypes and 3 p23 genotypes. Furthermore, MPSP genotype-specific PCR methods were developed in this study and wide distributions of 5-district genotypes of T. orientalis were observed for the examined farms. Our results indicate that at least 5 types of T. orientalis exist in Kumamoto and Okinawa prefectures of Japan and that genotype-specific PCR assays are highly applicable for the quarantine of transported cattle and for epidemiological surveys of bovine theileriosis in Japan.  相似文献   
264.
265.
ABSTRACT:   Estrogen receptor (ER) cDNA was cloned from the liver of common Japanese conger Conger myriaster . Common Japanese conger ER cDNA contains 2543 nucleotides including an open reading frame that encodes 596 amino acids, with a molecular weight of 66.1 kDa. The deduced amino-acid sequence of the common Japanese conger ER shares 85% identity with that of eel Anguilla japonica ER-β, and 39–46% and 53–59% identity with the deduced sequences of ER-α and ER-β of other species, respectively. In a phylogenetic analysis, the common Japanese conger ER was found to cluster with the ER-β of other species. The common Japanese conger ER-β also has six domains (A–F), which are conserved in the nuclear receptor superfamily. The amino-acid sequences in the C and E domains were highly conserved between common Japanese conger ER-β and other ER. However, the other domains showed low homology. In the female common Japanese conger, ER-β mRNA was highly expressed in the liver and pituitary gland. The expression levels of the ER-β gene increased from the oil droplet stage to the primary yolk globule stage and were maintained until the migratory nucleus stage.  相似文献   
266.
Eriko  ABE  Kazunori  HAYAKAWA  Meiko  KIMURA  Ikuo  KIMURA  Nobuo  SEKI 《Fisheries Science》2003,69(3):605-614
ABSTRACT:     Formaldehyde (FA)-induced denaturation of myofibrillar proteins and its prevention were investigated by means of measuring the solubility, adenosine triphosphatase (ATPase) activity, and thermal gel formability of myofibrils and surimi proteins in the presence and absence of free amino acids and glutathione, reduced form. The addition of FA decreased the solubility of myofibrils in 0.5 M NaCl at pH 7.0 and 0°C depending on its concentration and incubation time. The solubility decrease was completely inhibited by the presence of equal, twofold, and threefold amounts of cysteine (Cys), glutathione, and histidine (His) to the amount of FA, respectively. Myofibrillar Ca-ATPase was markedly activated at the initial phase and then decreased later by the addition of FA. The K-ATPase was inactivated with an increase in the amount of FA. The FA-induced changes in both ATPase activities were inhibited in the presence of Cys and His. Thermal gel formability of surimi paste increased only in a short period after the addition of a low concentration of FA. Practically, FA inhibited the thermal gelation and setting effect through the inactivation of transglutaminase. In the presence of Cys, His or glutathione, a strong elastic surimi gel was produced because FA-induced detrimental effects were inhibited.  相似文献   
267.
Indole-3-carbaldehyde (1) was isolated as a tyrosinase inhibitor from the ethyl acetate-soluble fraction of extracellular fluids of unknown fungus YL185. The partial sequencing data of 18S ribosomal DNA (18S rDNA) indicate that this isolate belongs to the family Polyporaceae or Corticiaceae sensu lato. Indole-3-carbaldehyde inhibited the oxidation of l-3,4-dihydroxyphenylalanine (l-DOPA) by mushroom tyrosinase with a 50% inhibitory concentration (IC50) of 1.3mM and showed inhibitory activity on melanin production in B16 melanoma cells. The aldehyde group of 1 plays an important role in eliciting tyrosinase inhibitory activity.  相似文献   
268.
Natural durability of two plantation woods, Chinese fir and I-214 poplar, was investigated thoroughly by three testing methods, namely an accelerated laboratory decay test, a fungus cellar test and a field test. Aft er the decay test using Postia placenta and Trametes versicolor, Chinese fir and the I-214 poplar showed 34% and 69% of mass loss, respectively, indicating they should be classified as slightly durable and non-durable wood. This conclusion was confirmed by the fungus cellar test and the field test. Like the performance in the decay test, I-214 poplar showed no resistance to termites either in the laboratory or in the field,whereas Chinese fir would be classified as moderately resistant.  相似文献   
269.
The development of cleavage stage preimplantation embryos is disrupted by exposure to heat shock, such as high temperatures in the summer season. In this study, we investigated whether addition of anthocyanins, which are strong scavengers of reactive oxygen species (ROS), improves development and intracellular redox status of heat-exposed bovine preimplantation embryos by reduction of heat shock-derived oxidative stress. After in vitro fertilization (IVF), embryos were cultured at 38.5 C through Day 8 (Day 0=day of IVF) with 0, 0.1, 1 and 10 microg/ml anthocyanins (non-heat-shocked group). On Day 2, embryos were cultured at 41.5 C for 6 h with 0, 0.1, 1 and 10 microg/ml anthocyanins followed by culture at 38.5 C until Day 8 (HS group). After exposure to heat shock, the intracellular ROS and glutathione (GSH) contents of individual embryos were measured in the non-heat-shocked and HS groups using fluorescent probes. On Day 8, the blastocysts formation rates of the embryos and total cell numbers of blastocysts were evaluated. Embryos exposed to heat shock without anthocyanins showed a significant decrease in blastocyst formation rate and GSH content (P<0.05) and an increase in intracellular ROS (P<0.05) compared with non-heat-shocked embryos. In contrast, addition of 0.1 microg/ml anthocyanins significantly (P<0.05) improved the blastocyst formation rate of the heat-shocked embryos. Addition of any dose of anthocyanins produced a significant decrease in the ROS levels (P<0.05) and tended to increase the GSH levels under heat-shock conditions. However, addition of higher concentrations (1 and 10 microg/ml) of anthocyanins to the culture media under heat shock did not improve the development of embryos. These results indicate that anthocyanins maintain the intracellular redox balance of heat-shocked bovine embryos by reducing intracellular oxidative stress and increasing the GSH levels. Thus, alterations of the redox state using natural antioxidative polyphenols is a useful approach for reducing heat shock-derived oxidative stress.  相似文献   
270.
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