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Photosynthesis is reversibly inhibited by exposing plants to SO2. The formation of α-hydroxy sulfonate in the exposed plants is suggested as one of the effects, because this compound inhibits glycolic oxidase which is necessary in the glycolic acid pathway. The suppression of the glycolic acid path should affect various aspects of metabolism in plants, particularly the reduction of the biosynthesis of glycine and serine. In this paper, the biosynthesis of these amino acids in plants exposed to SO2 was investigated to estimate the significance of the formation of α-hydroxy sulfonate in the plants. The results show that photosynthetic formation of serine was reduced in the exposed plants, and that α-hydroxy sulfonate was formed.  相似文献   
3.
The emulsifying properties of porcine sarcoplasmic protein (SP) with or without low-molecular weight surfactants were examined. The emulsifying activity (EA) of SP was weaker than that of sodium caseinate (CA), blood plasma (BP) and whey protein isolates at a protein concentration of 0.5–3%. Sodium chloride decreased the EA of SP. The EA of SP was about one quarter that of CA in the presence of 3% sodium chloride. As homogenization time increased, the EAs of SP and BP decreased. The EA of SP was not influenced by sucrose stearate ester (SE) with a hydrophilic-lipophilic balance (HLB) value of 16 (SE-16) but was decreased by those with HLB values of 5 and 1. Low-molecular weight surfactants such as SE-16, Tween 80 and sodium cholate improved the EA of SP with the two-step emulsification method: corn oil was previously emulsified with the surfactant before addition of SP and homogenization. In the case of the addition of SE-16 as primary emulsifier, the EA was about twice as high as that of SP alone. The same effect was shown in the emulsions formed by CA and soy protein isolate. These results indicate that the emulsifying properties of meat protein would be improved by the addition of a low-molecular weight surfactant in a two-step emulsification.  相似文献   
4.
The development and distribution of lymphocyte subsets in calf palatine and pharyngeal tonsil were examined. During prenatal development, B cells were distributed in the subepithelial area, and T cells and MHC class II+ cells were found in the deep layer of B-cell area, respectively, in both tonsils. At neonatal stage, lymphoid follicle containing a few CD4+ cells have been formed in both tonsils. IgG+ and IgA+ cells were found in the parafollicular and epithelial area. At 3 months old, many germinal centers were recognized in both tonsils. CD4+ cells and IgG mRNA expression were detected in light zone of germinal centers. Many IgG, and IgA mRNA expressions also could be detected in the parafollicular and subepithelial area of both tonsils. The data suggest that both tonsils have an important role of local immune defense against invading antigen after birth. The comparison of the histological characteristics of tonsil and Peyer's patch during ontogeny is also discussed.  相似文献   
5.
We evaluated whether a bovine intestinal epithelial (BIE) cell line could serve as a useful in vitro model system for studying antiviral immune responses in bovine intestinal epithelial cells (IECs) and for the primary screening of immunobiotic microorganisms with antiviral protective capabilities. Immunofluorescent analyses revealed that toll-like receptor 3 (TLR3) was expressed in BIE cells, and the results of real-time quantitative PCR showed that these cells respond to stimulation with poly(I:C) by up-regulating pro-inflammatory cytokines and type I interferons. In addition, we demonstrated that BIE cells are useful for the primary screening of immunobiotic lactic acid bacteria strains which are able to beneficially modulate antiviral immune responses triggered by TLR3 activation in bovine IECs. The characterization of BIE cells performed in the present study represents an important step towards the establishment of a valuable bovine in vitro system that could be used for the development of immunomodulatory feed for bovine hosts.  相似文献   
6.
Carbon dioxide (CO2) flux was measured above the forest at the Fujiyoshida site on the northern slope of Mount Fuji in Japan in 2000?C2008 using an eddy covariance technique. The forest mainly consists of Japanese red pine (Pinus densiflora) and Japanese holly (Ilex pedunculosa). The 9-year average of monthly mean net ecosystem production (NEP) ranged from ?0.1?g?C?m?2?day?1 in January to 2.5?g?C?m?2?day?1 in May. The maximum net uptake was observed in May, although gross primary production (GPP) was highest in July. Variation in the leaf amount did not notably affect seasonal variation in GPP. This site was characterized by carbon uptake even in winter, if the meteorological conditions were conducive for photosynthesis and a resulting long period of carbon uptake. The 9-year averages of annual NEP, GPP, and ecosystem respiration (RE) were 388, 1,802, and 1,413?g?C?m?2?year?1, respectively. The annual NEP was lowest in 2003 and highest in 2004 over the 9?years. Year-to-year variability of NEP mainly depended on air temperature and photosynthetically active radiation in summer, and the dependence of the deviation of annual NEP on that of GPP was greater than that of RE. Long-term observational data indicated that the carbon uptake ability at the study site was at a moderate level in comparison with other temperate humid evergreen forests around the world. These data also indicated that the site had a high carbon uptake ability compared with other deciduous forests in Japan because of the duration of carbon uptake.  相似文献   
7.
Cytochrome P450 (CYP) is important for metabolism of not only xenobiotics such as drugs, but also endogenous compounds including arachidonic acids. CYP4A11, CYP4F3v2, CYP4F11, and CYP4F45 have been identified in cynomolgus macaque, an animal species widely used for investigation of drug metabolism due to its evolutionary closeness to human. However, their metabolic functions have not been investigated. In this study, proteins were heterologously expressed in Escherichia coli and characterized by metabolic assays using arachidonic acids as substrates that are metabolized by CYP4 isoforms in human. The results showed that all four CYPs metabolized arachidonic acids. Therefore, cynomolgus macaque CYP4A11, CYP4F3v2, CYP4F11, and CYP4F45 are functional enzymes.  相似文献   
8.
Reptiles are one of the fastest growing sectors in the United States pet industry. Reptile‐associated salmonellosis (RAS) continues to be an important public health problem, especially among children. We investigated an outbreak of human Salmonella infections resulting from serotypes Cotham and Kisarawe, predominately occurring among children. An outbreak of illnesses was identified in persons with exposure to pet bearded dragon lizards. Human and animal health officials, in cooperation with the pet industry, conducted epidemiologic, traceback and laboratory investigations. Onsite sampling was conducted at two US breeding facilities, one foreign breeding facility, and a large pet retail chain. A total of 166 patients in 36 states were identified with illness onset dates from 02/2012–06/2014. The median patient age was 3 years (range, <1–79 years), 57% were aged ≤5 years, and 37% were aged ≤1 year. Forty‐four patients (37%) were hospitalized, predominantly children. Sampling at breeding facilities and a national pet store chain resulted in isolation of outbreak serotypes at each facility; isolation proportions ranged from 2%–24% of samples collected at each facility.Epidemiologic, microbiologic and traceback evidence linked an outbreak of uncommon Salmonella serotypes to contact with pet bearded dragons. The high proportion of infants involved in this outbreak highlights the need to educate owners about the risk of RAS in children and the potential for household contamination by pet reptiles or their habitats. Strategies should be developed to improve breeding practices, biosecurity and monitoring protocols to reduce Salmonella in the pet reptile trade.  相似文献   
9.
A 9-year-old female Pug was presented to us with chronic diarrhea. Hematologic findings indicated severe hypoproteinemia and hypoalbuminemia, and endoscopy revealed severe edema of the duodenal mucosa. Based on these results and on additional histopathological findings, we made a diagnosis of protein-losing enteropathy caused by lymphocytic-plasmacytic enteritis with lymphangiectasia. The dog was initially treated with prednisolone and cyclosporine. This treatment regimen was not effective. However, when methotrexate was substituted for cyclosporine, progress was obtained and the diagnosis was confirmed.  相似文献   
10.
The root systems of forest trees are composed of different diameters and heterogeneous physiological traits. However, the pattern of root respiration rates from finer and coarser roots across various tropical species remains unknown. To clarify how respiration is related to the morphological traits of roots, we evaluated specific root respiration and its relationships to mean root diameter (D) of various diameter and root tissue density (RTD; root mass per unit root volume; gcm(-3)) and specific root length (SRL; root length per unit root mass; mg(-1)) of the fine roots among and within 14 trees of 13 species from a primary tropical rainforest in the Pasoh Forest Reserve in Peninsular Malaysia. Coarse root (2-269mm) respiration rates increased with decreasing D, resulting in significant relationships between root respiration and diameter across species. A model based on a radial gradient of respiration rates of coarse roots simulated the exponential decrease in respiration with diameter. The respiration rate of fine roots (<2mm) was much higher and more variable than those of larger diameter roots. For fine roots, the mean respiration rates for each species increased with decreasing D. The respiration rates of fine roots declined markedly with increasing RTD and increased with increasing SRL, which explained a significant portion of the variation in the respiration among the 14 trees from 13 species examined. Our results indicate that coarse root respiration in tree species follows a basic relationship with D across species and that most of the variation in fine root respiration among species is explained by D, RTD and SRL. We found that the relationship between root respiration and morphological traits provides a quantitative basis for separating fine roots from coarse roots and that the pattern holds across different species.  相似文献   
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