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排序方式: 共有589条查询结果,搜索用时 281 毫秒
531.
Kim SB Kim SJ Lee BM Han YW Rahman MM Uyangaa E Kim JH Choi JY Yoo DJ Kim K Eo SK 《Veterinary microbiology》2012,155(2-4):172-182
Enhancing and/or modulating innate and adaptive immunity by cytokines appears to be greatly useful to provide effective protective immunity against infectious diseases. However, an effective delivery system for mass administration in livestock industry is needed because of limitations such as cost, labor, time, and protein stability. Here the immunomodulatory functions of swine interleukine-18 (swIL-18), known as IFN-γ-inducing factor (IGIF), were evaluated in a vaccination model of pseudorabies virus (PrV) using attenuated Salmonella enterica serovar Typhimurium as the oral delivery system. The oral administration of S. enterica serovar Typhimurium expressing swIL-18 prior to vaccination with inactivated PrV vaccine induced enhanced levels of serum PrV-specific IgG and its IgG2 isotype, compared to administration of S. enterica serovar Typhimurium harboring the empty vector. Furthermore, S. enterica serovar Typhimurium expressing swIL-18 mounted Th1-biased cellular immune responses against PrV antigen, as evaluated by the production of IFN-γ and IL-4 from peripheral blood mononuclear cells of piglets. Subsequently, Th1-biased immunity induced by S. enterica serovar Typhimurium expressing swIL-18 showed rapid response and rendered piglets displayed more alleviated clinical signs following the virulent PrV challenge. Also, this alleviation of clinical signs was further confirmed by the reduction of nasal excretion of PrV after challenge. The present study demonstrates the extended use of immunomodulatory functions of swIL-18 orally delivered by attenuated S. enterica serovar Typhimurium. 相似文献
532.
Md. Sakhawat Hossain Nadia Mahjabin Sony Shunsuke Koshio Manabu Ishikawa Sohel Mian Vikas Kumar 《Aquaculture Nutrition》2021,27(1):187-197
Purine nucleotides regulate the cellular functions in the animal body. The current study evaluates the comparative efficacy of dietary purine nucleotides, that is, adenosine monophosphate (AMP), guanosine monophosphate (GMP) and inosine monophosphate (IMP) in red sea bream Pagrus major. Semi‐purified basal diet was formulated (Control, D1) containing 550 g/kg protein, supplemented with purine nucleotides AMP, GMP and IMP at their optimum supplementation level (2, 4 and 4 g/kg) to formulate the experimental diet groups D2, D3 and D4, respectively. Initial weight of 3.5 ± 0.01 g fish was randomly fed test diets in triplicate. After 56 days, % weight gain (p = .003), specific growth rate (p = .003) and apparent lipid digestibility (p = .04) were significantly higher in fish fed diet group D4 followed by D3 and D2. Supplemented groups showed significantly higher feed intake in comparison to control (p = .001). Supplemented groups showed significantly increased and decreased NBT (p = .003) and CAT (p = .003) activity, respectively. Fish fed IMP supplemented diets had significantly lower blood urea nitrogen (p = .04), glutamyl oxaloacetic transaminase (p = .04) and glutamic‐pyruvate transaminase (p = .001) followed by other supplemented groups. Supplemented diet groups showed enhanced stress resistance. Interestingly, D2 and D4 groups showed best oxidative stress status of fish. Therefore, these results indicated that among purine nucleotides, supplementation of IMP could be a more effective nucleotide as functional supplement in red sea bream diet. 相似文献
533.
Md. Tofazzal Islam Mitsuyoshi Sakasai Yasuyuki Hashidoko Abhinandan Deora Yasuko Sakihama Satoshi Tahara 《Journal of General Plant Pathology》2007,73(5):324-329
A modified medium was used to culture mycelium and produce a large quantity of zoospores of Aphanomyces cochlioides, a principal pathogen of damping-off disease of sugar beet and root rot disease of spinach. The semisolid medium consisted
of 17 g corn meal agar (CMA) added with 4 g of yeast extract (YE) per liter of 50 mM phosphate buffer (pH 6.8–7.0). This medium
supported the production of ca. 106 zoospores ml−1 in 6-day-old cultures, approximately 11-fold higher than the commonly used CMA (17 g CMA per liter of water, pH 6.0 ± 0.2).
Although morphological characters of the zoospores produced from the hyphae grown on CMA and CMA + YE were almost similar,
they contrasted their developmental strategy after encystment induced by mechanical agitation. Cystospores originating from
the zoospores on CMA regenerated zoospores (>80%), while those from CMA + YE germinated (ca. 80%) and produced hyphae. Furthermore,
4–10% of the germinated cystospores on CMA + YE had double germ tubes. The soluble protein profiles of zoospores produced
on CMA and on CMA + YE demonstrated that several proteins were either different or expressed differently. Our results suggest
that the culture medium directly influences zoosporogenesis in A. cochlioides hyphae and the developmental strategy of the produced zoospores. 相似文献
534.
Md. Arifur Rahman MAZUMDER Hajime KUMAGAI Katsunosuke MITANI 《Animal Science Journal》2004,75(4):333-338
Diversity of chemical composition, in vivo digestibility and in situ dry matter degradability of oat hay (Avena sativa) were studied. Oat hay samples obtained from 22 batches imported were analyzed for chemical composition. The result showed a wide range of variations in crude protein (3.9–8.8%, on a dry matter basis), crude fiber (22.1–35.2%), nitrogen free extract (50.0–66.0%), organic cellular contents (23.4–40.0%), organic cell wall (53.1–70.8%), organic a (4.1–9.8%), organic b (49.0–63.8%) fractions and the estimated total digestible nutrients (50.3–63.8%) from the organic components. Of these, four oat hay samples were used for the measurement of dry matter intake, in vivo digestibility and in situ dry matter degradability in sheep. Significant differences were observed for the dry matter intake, in vivo digestibility of dry matter, crude protein, crude fiber and nitrogen free extract, dry matter disappearance at 48 h and effective degradability at k = 0.05 h?1 of the samples (P < 0.05). The results revealed a wide range of diversity of nutritional quality of the imported oat hay that could have an affect on production potential in animals. 相似文献
535.
Sensing and Uptake of Nitrogen in Rice Plant: A Molecular View 总被引:1,自引:0,他引:1
Md Saiful ISLAM 《水稻科学》2019,26(6):343-355
As a main feature of plant autotrophy, assimilation of inorganic nitrogen(N) is not only of fundamental interest to the crop, but also a crucial factor in crop productivity. N is the main plant mineral nutrient needed for chlorophyll production and other plant cell components(proteins, nucleic acids and amino acids). I highlighted the novel aspects of N responsive sensors, transporters and signaling molecules recently identified in the monocot rice plant, and discussed their potential roles in N sensing and transporting. Furthermore, over the last couple of years, N sensing has been shown to be affected by different external factors, which act as local signals to trigger systemic signaling coordinated by long-distance transport or mobile signals in plant body. Understanding of this complex regulatory network provides a foundation mechanism for the development of novel strategies to increase the acquisition and transportation efficiency of nitrogen under varying N conditions for rice production. 相似文献
536.
537.
Md. Mijan Hossain Chiharu Tani Tomoko Suzuki Fumiko Taguchi Tatsuhiro Ezawa Yuki Ichinose 《Physiological and Molecular Plant Pathology》2008,72(4-6):122-127
Polyphosphate kinase (PPK), encoded by the ppk gene, is a principal enzyme responsible for synthesis of inorganic polyphosphate (poly P) from ATP in many Gram-negative bacteria. In order to elucidate the functions of poly P in Pseudomonas syringae pv. tabaci 6605, an in-frame deletion mutant of the ppk gene (ppk) was constructed. The ppk mutant did not accumulate poly P, whereas the wild-type strain accumulated a large quantity. The mutant had reduced swarming motility, even though it retains swimming motility like the parental strain. The mutant exhibited increased sensitivity to prolonged incubation and environmental stresses, such as heat shock and oxidative stress and reduced exopolysaccharide (EPS) production compared to the wild-type. Northern blot analysis revealed that expression of the rpoS gene, encoding the stationary phase sigma factor RpoS, was reduced in ppk in the logarithmic phase, indicating that rpoS is regulated by the ppk gene. The poly P deficient mutant had significantly reduced ability to cause disease in its host tobacco plant and in planta growth of the mutant was also significantly reduced in host tobacco leaves as compared to the wild-type strain. Thus, our results suggest that poly P plays an important role in the virulence of P. syringae pv. tabaci 6605. 相似文献
538.
Poor grain filling induced by waterlogging is similar to that in abnormal early ripening in wheat in Western Japan 总被引:3,自引:0,他引:3
Abnormal early ripening (AER), a major constraint on wheat production in Western Japan, manifests as sudden leaf senescence shortly after anthesis and results in poor grain filling; this leads to smaller grains and reduced grain yield. It is suggested that overwetting of the soil may be related to AER. We conducted field experiments over 2 seasons (2008-2009 and 2009-2010) in Yamaguchi, Western Japan, with waterlogging treatment using 2 Japanese wheat cultivars, Daichinominori (Western Japanese cultivar) and Haruyutaka (Hokkaido cultivar), which differ in terms of grain growth in the environment of Western Japan. We imposed pre-anthesis waterlogging for 2 weeks in 2008-2009 and post-anthesis waterlogging throughout the grain-filling period in 2009-2010. Pre-anthesis waterlogging had no significant effect on grain yield or grain filling irrespective of cultivar. Post-anthesis waterlogging severely reduced the grain yield by 44% and 36% in Haruyutaka and Daichinominori, respectively. The yield loss was attributable to the smaller grain weight that was a result of slower grain growth rate later in the shortened grain-filling period. Post-anthesis waterlogging induced sudden leaf senescence 1 and 2 weeks after anthesis in Haruyutaka and Daichinominori, respectively, and drastically reduced the photosynthesis and ultimately dry mass accumulation. It also depressed the remobilization of water-soluble carbohydrates (WSCs) from culms to grains leaving more residual WSCs in the culms at harvest (149 and 65 mg g−1 DW in waterlogging and controls, respectively). The results indicate that the reduced grain growth due to waterlogging was attributable to decreased current assimilation and poor remobilization of culm WSCs to grain similar to that in AER plants. These results suggest that injured root function after anthesis might induce early leaf senescence and poor grain filling similar to AER wheat. 相似文献
539.
Soil slaking is an environment-friendly technique that is gaining importance in restoring saline soils. The objective of this
article is to evaluate the effect of initial water content (IWC) on saturated hydraulic conductivity (K
s) in desalinization with slaking and drying. Accordingly, a slaking test was carried out during February, 2009 for evaluating
the effects of slaking and drying on K
s, sodium adsorption ratio (SAR) and exchangeable sodium percentage (ESP) under various IWC. We prepared natural and air-dried
soils of paddy field in Kojima Bay Polder, Japan to give different pre-drying, air-dried, and not dried (natural). The air-dried
soils were resaturated. Each soil was well mixed, then dried to different initial moisture contents (60, 50, 40, 30, 20, and
10% by weight). The specimens were immersed into water in the pot for 24 h. The K
s was measured, and cations in slaked and unslaked soils were analyzed. The K
s was high under the water content below 30% in both the natural and the air-dried soils. But the effects were more pronounced
in the natural soil. The air-dried soil showed far smaller K
s than the natural soil. In outer solution, the highest SAR was noted at 30% in the natural and 30 and 20% in the air-dried
soils. Significant decrease in ESP of the soils (slaked + unslaked) was also observed at the same water content. Lower water
content was more effective in decreasing the soil ESP after desalinization from saline soil. The natural soil showed lower
ESP and higher porosity, which was considered as a reason for higher K
s of natural soil than that of air-dried soils. The results indicated that lower water content (10–30%) had no hazardous effect
on K
s by slaking and drying of soil. 相似文献
540.
Hyun Ah Jung Md. Nurul Islam Chan Mee Lee Hyong Oh Jeong Hae Young Chung Hee Chul Woo Jae Sue Choi 《Fisheries Science》2012,78(6):1321-1329
In the present study, we investigated the antidiabetic potential of fucoxanthin via the inhibition of rat lens aldose reductase (RLAR), human recombinant aldose reductase (HRAR), advanced glycation end-product (AGE) formation, protein tyrosine phosphatase 1B (PTP1B), and α-glucosidase. Fucoxanthin displayed potent inhibitory activity against AGE formation and HRAR and RLAR activity. In addition, fucoxanthin showed potent inhibitory activity against PTP1B. However, it did not show α-glucosidase inhibitory activity below 200 μM. In addition, our kinetic study revealed that fucoxanthin competitively inhibited RLAR, while it showed mixed-type inhibition against PTP1B. In order to confirm enzyme inhibition, we predicted the 3D structure of PTP1B using Autodock 4.0 to simulate the binding of fucoxanthin. Docking simulation results demonstrated that three residues of PTP1B (Phe30, Phe52, and Gly183) interact with the two hydroxyl groups of fucoxanthin. In addition, the binding energy was negative (?7.66 kcal/mol), indicating that the three hydrogen bonds may stabilize the open form of the enzyme and potentiate tighter binding to the active site of PTP1B, resulting in more effective PTP1B inhibition. The results of the present study therefore clearly demonstrate the promising potential of fucoxanthin as a therapeutic intervention for the management of diabetes as well as diabetes-associated complications, which could be explored further. 相似文献