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111.
DNA immunization induces systemic humoral and cellular immune responses to the antigen encoded by cDNA in a plasmid DNA. In the present study, a plasmid DNA encoding cDNA of beta-galactosidase (beta-gal), pCAGGS-lacZ, was inoculated intramuscularly to a healthy dog in order to evaluate location and duration of the gene expression. On day 7, the plasmid DNA was found by PCR in the muscle where the plasmid was injected. Furthermore, beta-gal expression was detected in the same muscle sample by beta-gal staining. However, the plasmid DNA was not detected in any samples collected on days 14, 21 and 28. The present results suggest that duration of the gene expression of beta-gal by the plasmid DNA is limited in the muscle in dogs and an efficacy for a gene expression should be evaluated depending on the gene inserted in the plasmid DNA for immunotherapy.  相似文献   
112.
Three dogs clinically diagnosed with allergic rhinitis (AR) were examined for their immunological findings. House dust mites (HDM) such as Dermatophagoides farinae (DF) and D. pteronyssinus (DP) were identified as positive allergens in the 3 dogs with both intradermal skin test and serum antigen-specific IgE test. Lymphocyte blastogenic response of peripheral blood mononuclear cells (PBMCs) under stimulation with DF antigen in dogs with AR was higher than that in 4 healthy control dogs. Expression level of IL-4 mRNA in PBMCs obtained from the 3 AR dogs was higher than that in PBMCs obtained from 4 healthy control dogs before and after stimulation with DF antigen. Expression level of IFN-gamma mRNA in PBMCs was not different between the AR and control dogs before and after stimulation with DF antigen. These results suggested that allergic reaction to HDM antigen and T(H)2-type immune response were associated with the development of AR in 3 dogs examined in this study.  相似文献   
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We investigated the efficacy of genetically modified yeast (GMY) phytase on phosphorus (P) bioavailability in growing pigs fed a corn–soybean meal based diet. Crossbred barrows were fed a P-adequate, a low-P or a P-deficient diet containing 0.37, 0.27 and 0.14% non-phytate-P, respectively. The P-deficient diet was supplemented with wild-type yeast (WTY), Aspergillus (ASP) or GMY phytase at 750 PU per kilogram of food. Dietary ASP and GMY phytases increased plasma inorganic P (Pi) concentration and the apparent absorption of P, and decreased the concentration of a bone resorption marker, plasma type-I collagen C-terminal telopeptide (ICTP). Wild-type yeast phytase also increased the apparent absorption of P, but the changes in plasma Pi and ICTP concentrations were not significant. Although the dietary Pi-equivalencies based on plasma Pi and ICTP concentrations did not differ between WTY and ASP phytases, the equivalency of ASP phytase based on apparent absorption of P was higher than that of WTY phytase. The equivalency of GMY phytase calculated from each parameter was higher than that of WTY phytase, and did not differ from that of ASP phytase. These results suggest that efficacy of GMY phytase on P bioavailability was higher than WTY phytase, and as effective as ASP phytase in growing pigs.  相似文献   
115.
AIM: To explore the effect of dual PI3K/Akt/mTOR inhibitor NVP-BEZ235 on autophagy of polycystic kidney (PCK) rat cholangiocytes. METHODS: The protein levels of p-mTOR and p-Akt in the bile duct epithelial cells were examined by immunohistochemistry. The effect of NVP-BEZ235 on the viability of cholangiocytes was detected by WST-1 assay. The levels of PI3K/Akt/mTOR signaling pathway and autophagy-related proteins with NVP-BEZ235 treatment were determined by Western blot. The effects of LC3 and Beclin 1 silencing, and authophagy-specific inhibitor 3-methyladenine (3-MA) on the cell viability were analyzed by WST-1 assay. RESULTS: The protein levels of p-Akt and p-mTOR were highly increased in the bile duct epithelium of the PCK rats. NVP-BEZ235 significantly inhibited the viability of the cholangiocytes in a dose- and time-dependent manner (P<0.05). NVP-BEZ235 significantly reduced the levels of PI3K/Akt/mTOR signaling pathway-related proteins in the PCK rat cholangiocytes. NVP-BEZ235 upregulated the autophagy-specific proteins LC3 II and Beclin 1. The inhibitory effect of NVP-BEZ235 on the cell viability was weakened by treatment with 3-MA and knockdown of LC3 and Beclin 1 (P<0.01).CONCLUSION: The PI3K/Akt/mTOR inhibitor NVP-BEZ235 suppresses the viability of PCK rat cholangiocytes, and the mechanism is closely related with autophagy.  相似文献   
116.
The present study examined the effects of substituting kraft pulp (KP) with corn silage (CS) on dry matter intake (DMI), ruminal mat and rumen fermentation characteristics, and rumination. Four non‐lactating, rumen‐cannulated Holstein cows were fed a CS diet comprising 36% grass silage (GS) and 64% CS or a KP diet comprising 36% GS, 57% KP, and 7% soybean meal. DMI was significantly lower in cows fed the KP diet than in those fed the CS diet (< 0.05), whereas rumination time did not significantly differ between the treatments. Dry matter content in the rumen immediately before and 3 h after feeding was significantly higher in cows fed the KP diet than in those fed the CS diet (< 0.05). The consistency and thickness of the ruminal mat did not significantly differ between the treatments. The ruminal mean retention time of feed particles tended to be longer in cows fed the KP diet than in those fed the CS diet (p < 0.10). The ruminal digestion rate of KP was comparable to that of GS and CS. Because ruminal mat was formed and rumination was stimulated, KP was considered to have the equivalent physical effectiveness as CS.  相似文献   
117.
Journal of General Plant Pathology - An easy, rapid method has been needed to test the pathogenicity of strains of Ralstonia pseudosolanacearum, the cause of serious bacterial wilt on ginger...  相似文献   
118.
Leaf litter respiration (R LL) was directly measured in situ to evaluate relationships with the water content in leaf litter (WC), which is distributed heterogeneously under natural conditions. To do so, we developed a small, closed static chamber system using an infrared gas analyzer, which can measure instantaneous R LL. This study focuses on the measurement of CO2 effluxes from leaf litter using the chamber system in the field and examines the relationship between R LL and WC among seven broadleaf species in a temperate forest. The measurements focused on the position of leaves within the litter layer, finding that both R LL and WC were significantly higher in the lower layer. The value of R LL increased with increasing WC, and the response of R LL to WC was similar among all seven species. Moreover, the temporal variation in WC differed among three species and was associated with leaf litter thickness. The observed heterogeneity in WC induced by the physical environment (e.g., position and thickness of leaf litter) affects the variation in WC and, therefore, both R LL and the decomposition rates of organic matter in the litter layer.  相似文献   
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Tenma  Hinako  Tsunekawa  Koki  Fujiyoshi  Riho  Takai  Hajime  Hirose  Masae  Masai  Nanami  Sumi  Kosuke  Takihana  Yuta  Yanagisawa  Sogen  Tsuchida  Kota  Ohara  Kenichi  Jo  Toshiaki  Takagi  Masaki  Ota  Akiko  Iwata  Hiroyoshi  Yaoi  Yuichi  Minamoto  Toshifumi 《Fisheries Science》2021,87(3):321-330

Outbreaks of bacterial cold-water disease (BCWD), caused by Flavobacterium psychrophilum, are widespread in Japan, especially among ayu Plecoglossus altivelis. There are few investigations of F. psychrophilum in river water, and its seasonal distribution has not been clarified. We aimed to identify the spatiotemporal dynamics of F. psychrophilum and ayu to provide information that is useful for establishing a countermeasure for BCWD. Quantitative analysis of environmental DNA (eDNA) was used to clarify the year-round dynamics of ayu and F. psychrophilum. We sampled river water from the Nagara and Ibi rivers in Japan, and conducted monthly water sampling and eDNA quantification. Changes in the eDNA concentration of ayu were consistent with the known life histories of the fish. There was a strong negative correlation between the eDNA concentration of F. psychrophilum and water temperature, suggesting a strong dependence of F. psychrophilum dynamics in the river on water temperature. Furthermore, relatively high eDNA concentrations were recorded for both organisms in early summer and fall, suggesting that ayu is infected with F. psychrophilum during these seasons when experiencing up- and downmigration, respectively.

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