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21.

While environmental pollution and destruction of nature are expanding on a global scale, it is becoming ever more important to comprehend the influence of human activities on the global environment and to consider the future. How does acid pollution caused by human activities influence the environment? When and how has it progressed, what is the situation now and how is it likely to shift in the future? Humans are creatures destined to consume energy and resources in the biosphere. Although we know that drastic and disproportionate increases in the consumption of natural and non-renewable resources have greatly altered the biosphere, reliable data on the actual levels of pollution existing in the past are scarce or lacking. Many methods involving natural or artificial materials have been used for historical monitoring, but there is still a need for new ones, which will allow us to look at the past and think of the future. The newly proposed scientific use of tree bark pockets as pollution time capsules gives us "new eyes" for historical monitoring of atmospheric pollution and changes in the global environment.

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22.
Strains of Xanthomonas campestris pv. vesicatoria Dye 1978 (Xcv), the causal agent of bacterial spot, have been classified into two groups based on their ability to hydrolyze starch. Three monoclonal antibodies (MAbs), 7AH10, 5HB3, and 4AD2, were produced immunized against the living bacteria and were specific to and could distinguish Xcv strains able or unable to hydrolyze starch (Amy+ or Amy). The MAb 7AH10, obtained against strain UPB141(Amy) reacted in an enzyme-linked immunosorbent assay with all the Amy strains (n = 19) and 1 of 11 Amy+ strains. Against Xcv 2625, an Amy unusual phenotype strain, MAb 5HB3, recognized 97% of our worldwide collection of Xcvs (n = 30). Also against that strain, the MAb 4AD2 reacted with none of the homologous Amy phenotypes and with 90% (n = 11) of the heterologous Amy+ phenotypes. For all the MAbs, cross reactions with other pathovars or species were less than 4% (n = 67). By assaying a Japanese collection of strains against the three MAbs, the Amy+ strains were distinguished from the Amy strains, and their relation with other world strains could be demonstrated. All the MAbs reacted with the lipopolysaccharide fraction of the bacterial cell wall during immunoblotting.  相似文献   
23.
Bacterial black spot disease of mango is caused by Xanthomonas campestris pv. mangiferaeindicae (Xcm), which consists of two genotypically and phenotypically distinct groups of strains. Monoclonal antibodies (MABs) were produced – 15 against CFBP 1717, a group I strain, and 9 against CFBP 2919 (yellow-pigmented), a group II strain – and were analyzed for their characteristics. On the avidin-biotin peroxidase complex enzyme-linked immunosorbent assay, the dilution limit of the MABs was between 100 and 200000 and was 10 times higher when measured on the corresponding ascitic fluid. All kinds of isotypes were represented among the MABs. All the Japanese Xcm strains, designated group I by hrp-restriction fragment length polymorphism (RFLP) analysis, reacted equally with MAB 1A7H12G3, which is the most specific for all but one worldwide group I strains, and to only one strain among group II. Also, to various extents, serological heterogeneity inside the two groups was consistently differentiated based on isozyme and RFLP analyses. MAB 1E2E1 against CFBP2919, because of its narrow specificity, and MAB 1A7H12G3 against CFBP1717, because of its broad specificity, will be useful for epidemiological studies or general control of the pathogen.  相似文献   
24.
25.
Data from 18 β‐carotene‐deficient Japanese Black cows were collected to clarify the effects of feeding β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin (Ig) in cows. Cows were assigned to control or carrot groups from 3 weeks before the expected calving date to parturition, and supplemental β‐carotene from dry carrots was 138 mg/day in the carrot group. Plasma β‐carotene concentrations in the control and carrot groups at parturition were 95 and 120 μg/dL, and feeding dry carrots slightly improved plasma β‐carotene at parturition. Feeding dry carrots increased colostral IgA concentrations in cows and tended to increase colostral IgG1, but colostral IgM, IgG2, β‐carotene and vitamin A were not affected by the treatment. Feeding dry carrots had no effects on plasma IgG1, IgA and IgM concentrations in cows, but plasma IgG1 concentrations decreased rapidly from 3 weeks before the expected calving date to parturition. These results indicate that feeding β‐carotene‐enriched dry carrots is effective to enhance colostral IgA and IgG1 concentrations in β‐carotene‐deficient cows.  相似文献   
26.
Tricholoma matsutake, a high-class edible mushroom in Japan, has been reported to have excellent biological activities, but difficulty in cultivating the fruit bodies and limited bulk availability have restricted detailed studies. We have developed a method of culturing in tanks, enabling the bulk supply of the mycelia. The preparation (CM6271) exerts modulative effects on the immune competence of mice and rats. In this study, a sodium hydroxide extract of CM6271 was defatted followed by fractionation with a combination of ion exchange chromatography and gel filtration in order to identify the components involved in the expression of the activity, and a single peak fraction (MPG-1) was obtained with reversed phase chromatography. MPG-1 was a glycoprotein (sugar:protein ratio, 94.3:5.7) with a relative molecular mass of 360 kDa, and the sugar moiety contained about 90% glucose. NMR spectra and methylation analysis revealed that the alpha-1,4-linkage was the predominant glucan linkage with alpha-1,6- and alpha-1,2-linkages in the minority. The amino acid composition in the protein moiety was rich in glutamine, alanine, asparagine, leucine, glycine, valine, serine, threonine, isoleucine, and proline. MPG-1 was resistant to degradation with amylase or protease. The oral administration of MPG-1 promoted, in a dose-dependent manner, the recovery of the mouse natural killer cell activity and serum IL-12 level that had been reduced by the loading of restraint stress. The dose of MPG-1 (25 mg/kg) required for the expression of the effect decreases to 1/12 of that of CM6271 (300 mg/kg). Furthermore, MPG-1 formed a complex with TGF-beta1 in vitro, modulating the biological activity of TGF-beta1 by binding to its active form. These results indicate that the mycelium of T. matsutake contains a novel alpha-glucan-protein complex with immunomodulatory activities.  相似文献   
27.
Typical heterocyclic compounds substituted with various functional groups found in Maillard reaction products were examined for antioxidant activity. Pyrroles exhibited the greatest antioxidant activity among all heterocyclic compounds tested. All pyrroles inhibited hexanal oxidation by almost 100% at a concentration of 50 microg/mL over 40 days. Addition of formyl and acetyl groups to a pyrrole ring enhanced antioxidative activity remarkably. Pyrrole-2-carboxaldehyde, 2-acetylpyrrole, 1-methyl-2-pyrrolecarboxaldehyde, and 2-acetyl-1-methylpyrrole inhibited hexanal oxidation by >80% at 10 microg/mL. Unsubstituted furan exhibited the greatest antioxidant activity among furans tested. Addition of all functional groups used in this study to furan decreased antioxidative activity. The antioxidant activity of thiophene increased with the addition of methyl and ethyl groups, but the addition of formyl or acetyl groups to thiophene decreased antioxidant activity. Thiazoles and pyrazines were ineffective antioxidants at all concentrations tested. Reaction of all heterocyclic compounds with hydrogen peroxide resulted in the formation of various oxidized products.  相似文献   
28.
We previously isolated a novel immunomodulatory alpha-(1,4)(1,6)(1,2)- d-glucan-protein complex (MPG-1) from mycelia of Tricholoma matsutake in basidiomycetes. In the present study, we raised a polyclonal antibody by immunizing rabbits with MPG-1 and constructed a sandwich enzyme-linked immunosorbent assay (ELISA) system to examine the distribution of MPG-1 among edible mushrooms and related processed foods. The system detected MPG-1 quantitatively at concentrations of more than 10 ng/mL, with a coefficient of variation of less than 10% by intra-assay and interassay precision. Analysis with the system of chemically modified MPG-1 suggested that the sugar moiety was mainly involved in the detection. The system detected MPG-1 in the extracts of the fruiting bodies of T. matsutake but not in those of 34 other basidiomycete species. Moreover, a significant amount of MPG-1 was detected in the extracts of their cultured mycelia. The antigenic structure of MPG-1 was relatively stable in terms of pH and temperature. MPG-1 was detected in processed foods supplemented with T. matsutake. These results suggest that MPG-1 is distributed predominantly in T. matsutake species and that the ELISA system can detect it in processed foods supplemented with T. matsutake.  相似文献   
29.
To understand the organic sulfur (S) stabilization in volcanic soils, we investigated organic S transformation rates and their relationships to soil properties in incubation experiments using forest soils from the Nikko volcanic region, central Japan. We hypothesized that carbon (C)-bonded S would first be transformed into ester sulfate-S and then into inorganic sulfate-S. We separately calculated the rates of decrease of C-bonded S (velocity 1, v 1) and ester sulfate-S (velocity 2, v 2) concentrations. During incubation, the ester sulfate-S concentration increased in two soils characterized by a high concentration of both ammonium oxalate-extractable aluminum (Alo) and pyrophosphate-extractable Al (Alp), whereas the C-bonded S concentration decreased in all soils. A large proportion of the S that was lost in the incubation experiments consisted of C-bonded S rather than ester sulfate-S. Velocity 2 was negatively correlated with both of Alo and Alp contents when soils were incubated at 20 °C. These results suggest that when C-bonded S is transformed into ester sulfate-S, complete mineralization to inorganic sulfate is inhibited, because ester sulfate-S is stabilized due to organo–mineral association. Incubation temperatures significantly affected v 2. Thus, production of inorganic sulfate by mineralization of ester sulfate-S appeared to be regulated by soil Al contents and temperatures. Velocity 1 was proportional to soil pH ranging from 4.5 to 5.5, indicating that the degradation of C-bonded S is pH dependent.  相似文献   
30.
The Freundlich isotherm was used to estimate the adsorption of the herbicide linuron on 39 Japanese soils to confirm the suitability of the prediction technique used in atrazine adsorption. Linuron was adsorbed on the soils according to the Freundlich isotherm. In conjunction with the log K F prediction equation derived from the soil characteristics, it was possible to predict the linuron adsorption. Comparison of the equations for linuron with those for atrazine, indicated that the difference in the intercept of the 1 / n regression line against log K F reflected the adsorptive characteristics of the herbicides.  相似文献   
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