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1.
The aim of the study was to determine the boron contents of some wild-growing mushrooms collected from the vicinity of several boron mines located in Balikesir, Turkey and compare the boron contents of some mushroom and soil samples. The locations of the mushroom samples collected were within the distance of 0–100, 100–500, and 500–1,000 m to the mines. Soil samples were taken from beneath randomly selected fungal fruit bodies. A total of 40 mushroom samples were found in the study area and 37 different species were identified. Among the 40 samples analyzed, the highest boron content was detected to be 273 mg kg−1 in Suillus collinitus. Also, Tricholoma terreum (69.52 mg kg−1), Myxomphalia maura (36.52 mg kg−1), Otidea concinna (30.70 mg kg−1), Sepultaria arenosa (28.94 mg kg−1), Melanoleuca paedida (28.33 mg kg−1), and Lycoperdon lividum (28.31 mg kg−1) relatively have high levels of boron and these species are proposed as candidates for boron accumulation. The boron contents of the other mushrooms varied and a pattern was observed where the boron content was found to be decreased as the distance from the mines increased.  相似文献   

2.
Immune response to liver-specific lipoprotein (LSP) is involved in the pathogenesis of chronic active hepatitis. Experimental hepatitis could thus be prepared in C57BL/6 mice by injection of liver-specific protein in a syngeneic liver homogenate with Freund's complete adjuvant. In hepatitic mice treated with maitake (Grifola frondosa) fruit bodies, the values of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) values increased temporarily by 2.24–2.79 times and decreased rapidly thereafter. However, in the mice given normal feed, both values increased constantly. Thus, we examined T cell activities both in the exacerbation and remission stages of hepatitis. We suggest that the activation of CD8+ cells is more potentiated than that of CD4+ cells by administration of maitake or the D-Fraction-glucan (β-1,6 glucan having β-1,3 branches), which can enhance immuno-competent cells at the exacerbation stage. However, at the remission stage, marked potentiation of CD8+ cell activity was not observed. These results suggest that depressed suppressor T cell activity is revived by the X-Fraction-glucan (β-1,6 glucan having α-1,4 branched glucan), while the cytotoxic T cell activity, which is activated by the D-Fraction, is restricted, thereby creating a smooth shift from the exacerbation stage to the remission stage.  相似文献   

3.
The Fusarium diversity and the mycobiota associated with moldy wheat kernels from Santa Fe province, Argentine, was assessed. The wheat cultivated area in Santa Fe province is divided according to agrometeorological conditions into two zones: Zone I (north-central) and Zone II (south). The natural occurrence of Fusarium toxins BEA, FUP, DON and NIV was also determined. Cladosporium was the most abundant of the 19 genera identified, followed by Fusarium, Phoma and Alternaria. Zone II shows a predominance of F. graminearum and F. culmorum. In Zone I, DON was present in 13/32 samples (range 0.43–3.60 mg kg−1) and NIV in 6/32 samples (range 0.11–0.40 mg kg−1). In zone II, DON was found in 11/21 samples (range 0.57–9.50 mg kg−1) and NIV in 4/21 samples (range 0.10–0.60 mg kg−1). BEA and FP were not detected in both zones.  相似文献   

4.
In a pot-soil culture ameliorative effect of sulphur (S) (0 or 40 mg S kg−1 soil) on cadmium (Cd) (0, 25, 50 and 100 mg Cd kg−1 soil)-induced growth inhibition and oxidative stress in mustard (Brassica campestris L.) cultivar Pusa Gold was studied. Cadmium at 100 mg kg−1 soil caused maximum increase in the contents of Cd and thiobarbituric acid reactive substances (TBARS) in leaves. Maximum reductions in growth (plant dry mass, leaf area), chlorophyll content, net photosynthetic rate (PN) and the contents of ascorbate (AsA), glutathione (GSH) were observed with 100 mg Cd kg−1 soil compared to control. The application of S helped in reducing Cd toxicity, which was greater for 25 and 50 mg Cd kg−1 soil) compared to 100 mg Cd kg−1 soil. Addition of S to Cd-treated plants showed decrease in Cd and TBARS content in leaves and restoration of growth and photosynthesis through increase in the contents of AsA and GSH. Net photosynthetic rate and plant dry mass were strongly and positively correlated with the contents of AsA and GSH. It is suggested that S may ameliorate Cd toxicity and protects growth and photosynthesis of mustard involving AsA and GSH.  相似文献   

5.
The tumor-inhibitory and liver-protective effects of crude extracellular polysaccharides (EPS) extracted from the liquid mycelial culture of the mushroom Phellinus igniarius were studied in mice. The mice were injected with murine sarcoma S180 and murine hepatoma H22. Crude EPS at 100, 200, 400 mg kg−1 body weight was administered to EPS groups each day in the twelve consecutive days. The result showed that EPS 200 mg kg−1 body weight significantly inhibited S180 and H22 at 65.0 and 46.3%, respectively. Moreover, EPS could not only keep the numbers of WBC, RBC, PLT and the concentration of HGB in a normal range, but also normalize the activities of AST, ALT and ALP. For example, in EPS-treated mice, AST significantly reduced with the percentage of A/G reverse in S180 (P < 0.05) and H22 (P < 0.01) when the mice took EPS 200 mg kg−1 body weight. In conclusion, it was remarkable that P. igniarius EPS exhibited antitumor activity related to dosage and protected liver function by sustaining the blood routine as well as keeping the blood biochemical indexes normal.  相似文献   

6.
The effects of seed maturity, media type, carbon source, and organic nutrient additives on seed germination, protocorm development, and plant growth of Paphiopedilum villosum var. densissimum Z. J. Liu et S. C. Chen were investigated. Micropropagation frequency was enhanced through the use of 200-day-old seed, Knudson C (KC) medium, and the presence of both glucose and coconut milk in the medium. The effects of various plant growth regulators on the frequency of shoot organogenesis in four Paphiopedilum species were also investigated. Explants of P. villosum var. densissimum and P. insigne (Lindl.) Stein incubated in the presence of 5 mg l−1 6-benzyladenine (BA) with 0.5 mg l−1 α-naphthalene acetic acid (NAA) and 0.2 mg l−1 BA with 0.1 mg l−1 NAA, respectively, showed a twofold increase in the frequency of shoot organogenesis. For explants of P. bellatulum (Rchb. f.) Stein and P. armeniacum S. C. Chen et F. Y. Liu, the combination of 5.5 mg l−1 BA with 0.5 mg l−1 NAA and 4 mg l−1 BA with 0.1 mg l−1 NAA, respectively, resulted in the highest frequencies of shoot organogenesis.  相似文献   

7.
Greenhouse experiments were conducted to study the permissible value of vanadium (V) based on the growth and physiological responses of green Chinese cabbage (Brassica chinensis L.), and effects of V on microbial biomass carbon (MBC) and enzyme activities in allitic udic ferrisols were also studied. The results showed that biomass of cabbage grown on soil treated with 133 mg V kg−1 significantly decreased by 25.1% compared with the control (P < 0.05). Vanadium concentrations in leaves and roots increased with increasing soil V concentration. Contents of vitamin C (Vc) increased by 10.3%, while that of soluble sugar in leaves significantly decreased by 54.0% when soil V concentration was 133 mg kg−1, respectively. The uptake of essential nutrient elements by cabbage was disturbed when soil V concentration exceeded 253 mg kg−1. Soil MBC was significantly stimulated by 15.5%, while dehydrogenase activity significantly decreased by 62.8% and urease activity slightly changed at treatment of 133 mg V kg−1 as compared with the control, respectively. Therefore, the permissible value of V in allitic udic ferrisols is proposed as 130 mg kg−1.  相似文献   

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10.
Interferon-alpha (IFN-α) is an immunomodulatory cytokine that is used clinically for the treatment of melanoma in the adjuvant setting. The cellular actions of IFN-α are regulated by the suppressors of cytokine signaling (SOCS) family of proteins. We hypothesized that the anti-tumor activity of exogenous IFN-α would be enhanced in SOCS1-deficient mice. SOCS1-deficient (SOCS1−/−) or control (SOCS1+/+) mice on an IFN-γ−/− C57BL/6 background bearing intraperitoneal (i.p.) JB/MS murine melanoma cells were treated for 30 days with i.p. injections of IFN-A/D or PBS (vehicle). Log-rank Kaplan-Meier survival curves were used to evaluate survival. Tumor-bearing control SOCS1+/+ mice receiving IFN-A/D had significantly enhanced survival versus PBS–treated mice (P = 0.0048). The anti-tumor effects of IFN-A/D therapy were significantly enhanced in tumor-bearing SOCS1−/− mice; 75% of these mice survived tumor challenge, whereas PBS-treated SOCS1−/− mice all died at 13-16 days (P = 0.00038). Antibody (Ab) depletion of CD8+ T cells abrogated the anti-tumor effects of IFN-A/D in SOCS1−/− mice as compared with mice receiving a control antibody (P = 0.0021). CD4+ T-cell depletion from SOCS1−/− mice also inhibited the effects of IFN-A/D (P = 0.0003). IFN-A/D did not alter expression of CD80 or CD86 on splenocytes of SOCS1+/+ or SOCS1−/− mice, or the proportion of T regulatory cells or myeloid-derived suppressor cells in SOCS1+/+ or SOCS1−/− mice. An analysis of T-cell function did reveal increased proliferation of SOCS1-deficient splenocytes at baseline and in response to mitogenic stimuli. These data suggest that modulation of SOCS1 function in T-cell subsets could enhance the anti-tumor effects of IFN-α in the setting of melanoma.  相似文献   

11.
The present study examined the effects of plant growth hormones, incubation period, biotic (Trametes versicolor, Mucor sp., Penicillium notatum, Rhizopus stolonifer, and Fusarium oxysporum) and abiotic (NaCl, MgSO4, FeSO4, ZnSO4, and FeCl3) elicitors on cell growth and α-tocopherol and pigment (red and yellow) productions in Carthamus tinctorius cell cultures. The cell growth and α-tocopherol and pigment contents improved significantly on Murashige and Skoog (MS) liquid medium containing 50.0 μM α-naphthalene acetic acid (NAA) and 2.5 μM 6-Benzyladenine (BA) at 28 days of incubation period. Incorporation of T. versicolor (50 mg l−1) significantly enhanced the production of α-tocopherol (12.7-fold) and red pigment (4.24-fold). Similarly, supplementation of 30 mg l−1 T. versicolor (7.54-fold) and 70 mg l−1 Mucor sp. (7.40-fold) significantly increased the production of yellow pigment. Among abiotic elicitors, NaCl (50–70 mg l−1) and MgSO4 (10–30 mg l−1) significantly improved production of α-tocopherol (1.24-fold) and red pigment (20-fold), whereas yellow pigment content increased considerably by all the abiotic elicitor treatments. Taken together, the present study reports improved productions of α-tocopherol and the pigment as a stress response of safflower cell cultures exposed to these elicitors.  相似文献   

12.
Silicate (Si) can enhance plant resistance or tolerance to the toxicity of heavy metals. However, it remains unclear whether Si can ameliorate lead (Pb) toxicity in banana (Musa xparadisiaca) roots. In this study, treatment with 800 mg kg−1 Pb decreased both the shoot and root weight of banana seedlings. The amendment of 800 mg kg−1 Si (sodium metasilicate, Na2SiO3·9H2O) to the Pb-contaminated soil enhanced banana biomass at two growth stages significantly. The amendment of 800 mg kg−1 Si significantly increased soil pH and decreased exchangeable Pb, thus reducing soil Pb availability, while Si addition of 100 mg kg−1 did not influence soil pH. Results from Pb fractionation analysis indicated that more Pb were in the form of carbonate and residual-bound fractions in the Si-amended Pb-contaminated soils. The ratio of Pb-bound carbonate to the total Pb tended to increase with increasing growth stages. Treatment with 100 mg kg−1 Si had smaller effects on Pb forms in the Si-amended soils than that of 800 mg kg−1 Si. Pb treatment decreased the xylem sap greatly, but the addition of Si at both levels increased xylem sap and reduced Pb concentration in xylem sap significantly in the Si-amended Pb treatments. The addition of Si increased the activities of POD, SOD, and CAT in banana roots by 14.2% to 72.1% in the Si-amended Pb treatments. The results suggested that Si-enhanced tolerance to Pb toxicity in banana seedlings was associated with Pb immobilization in the soils, the decrease of Pb transport from roots to shoots, and Si-mediated detoxification of Pb in the plants.  相似文献   

13.
The response of the aquatic plant Sparganium emersum to different sediment nutrient levels was studied in three mesocosm experiments. The aim was to assess plant growth parameters and nutrient accumulation in the plant tissue under conditions relevant for habitats with sediments affected by anthropogenic nutrient enrichment. The experimental treatments were produced by fertilisation of the rooting medium (washed river sand) with differing doses of either NPK mineral fertiliser or digested sludge from solid pig slurry waste. Growth inhibition by high nutrient levels was not observed in any treatment (highest nutrient concentrations in the sediment with mineral fertiliser: N 250 mg kg−1, P 50 mg kg−1; organic fertiliser: N 6300 mg kg−1, P 1800 mg kg−1), which confirms the tolerance of S. emersum to high nutrient loads. The sediment nutrient concentration was best reflected in shoot dry mass. Nutrient contents in plant tissues were similar for most nutrient concentrations in the rooting media; only N increased significantly with N levels in the sediment in belowground parts. Nutrient standing stocks in plants, however, generally corresponded to the nutrient supply, and reached highest values (max. N 3.7 g m−2, P 1.2 g m−2) in the richest treatments with organic fertiliser. The capability of S. emersum to use nutrients from high sediment concentrations and in organically polluted environments recommends this species for use in water quality management including tertiary wastewater treatment.  相似文献   

14.
Effects of selenium (Se) on growth and some physiological traits of roots in wheat (Triticum aestivum L. cv Han NO.7086) seedlings exposed to enhanced ultraviolet-B (UV-B) stress are reported. Responses of roots were different depending on the Se concentration. Compared with the control, root weight of wheat seedlings treated with 1.0 and 2.0 mg Se kg−1 soil increased by 39.47% and 16.28%, respectively. The lower amount Se (0.5 mg kg−1) and the higher amount Se treatments (3.0 mg kg−1) did not significantly affect on root weight. Se treatments significantly increased root activity, flavonoids and proline content, and activities of peroxidase and superoxide dimutase in wheat roots exposed to enhanced UV-B. In addition, the treatments with 0.5, 1.0, and 2.0 mg Se kg−1 significantly reduced malondialdehyde content and the rate of superoxide radical (O2) production of roots, whereas the higher amount Se treatment only induced a decrease in the rate of O2 production. The results of this study demonstrated that optimal Se supply promoted roots growth of wheat seedlings, and that optimal Se supply could reduce oxidative stress in wheat roots under enhanced UV-B radiation.  相似文献   

15.
Saussurea involucrata is a valuable traditional Chinese medicinal herb. This is the first report of a successful genetic transformation protocol for S. involucrata using Agrobacterium tumefaciens. Leaf explants were incubated with A. tumefaciens strain EHA105 harboring the binary vector pCAMBIA 1301, which contains the hpt gene as a selectable marker for hygromycin resistance and an intron-containing β-glucuronidase gene as a reporter gene. Following co-cultivation, about 23.7% of the explants produced hygromycin-resistant calli on MS basal medium (Murashige and Skoog in Physiol Plant 15: 473–497, 1962) supplemented with 1 mg l−1 benzyladenine (BA), 0.1 mg l−1 α-naphthaleneacetic acid (NAA), 0.1 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D), 20 mg l−1 hygromycin, and 500 mg l−1 cefotaxime. Shoots were regenerated following transfer of the resistant calli to shoot induction medium containing 1.5 mg l−1 BA, 0.1 mg l−1 NAA, 0.25 mg l−1 gibberellic acid (GA3), 20 mg l−1 hygromycin, and 250 mg l−1 cefotaxime, and about 67.5% of the resistant calli differentiated into shoots. Finally, 80% of the hygromycin-resistant shoots rooted on MS media supplemented with 0.2 mg l−1 NAA, 20 mg l−1 hygromycin, and 250 mg l−1 cefotaxime. The transgenic nature of the transformants was demonstrated by detection of β-glucuronidase activity in the primary transformants and by Southern blot hybridization analysis. About 16% of the total inoculated leaf explants produced transgenic plants after approximately 5 months. Using this optimized transformation system, a rice ortholog of the Arabidopsis FLOWERING LOCUS T gene, Hd3a, was transferred into S. involucrata. Introduction of this gene caused an early-flowering phenotype in S. involucrata.  相似文献   

16.
A protocol was developed for the micropropagation of Pinus massoniana and mycorrhiza formation on rooted microshoots. Seedling explants were first cultured on Gresshoff and Doy (GD) medium supplemented with 6-benzyladenine (BA) alone or in combination with α-napthaleneacetic acid (NAA) to stimulate the formation of intercotyledonary axillary buds. The frequency of axillary bud induction was up to 97% on medium supplemented with 4.0 mg l−1 BA and 0. 2 mg l−1 NAA, and the average number of buds per explant reached up to 5.5 on medium with 4.0 mg l−1 BA and 0.1 mg l−1 NAA. Axillary buds elongated rapidly after being transferred to half-strength GD medium containing activated charcoal (0.1% w/v). Shoot proliferation was achieved by cutting elongated shoots into stem segments and subculturing on GD medium containing 2 mg l−1 BA and 0.2 mg l−1 NAA. Root primordia were induced in 82% of shoots when transferred to half-strength GD medium containing 0.2 mg l−1 NAA. Root elongation was achieved in a hormone-free GD agar medium or a perlite substrate. Rooted plantlets were inoculated with the mycelium of ectomycorrhizal fungus Pisolithus tinctorius and the formation of ectomycorrhiza-like structures was achieved in vitro.  相似文献   

17.
An LC-MS method was developed for the analysis of triacylglycerols (TAG) in mouse liver extracts and plasma samples. C57 Mice were treated with two LXR agonists that have been shown to upregulate TAGs, T0901317 (T1317) or Org 264693 and compared to vehicle dosed animals. The dose used was 30 mg kg−1, once daily, with three different dose regimes; 24 H, 48 H and 5 day. The TAG ratios measured were C52:2/C54:3 and C52:3/C54:4, which corresponded to a decrease in the palmitate and an increase in oleate composition of the TAGs. A significant change in the C52:2/C54:3 ratio was observed with all dose regimes and a good correlation was obtained between liver and plasma samples. In a separate study, the same compounds were dosed to LXR α and LXR β knock-out (KO) mice at 30 mg kg−1, once daily, for 5 days. The LXR β KO mice showed similar TAG ratio changes to the C57 mice, whereas the LXR α KO mice showed no change in TAG ratios versus vehicle dosed animals. Measurements of lipid liability in response to an LXR agonist are typically made by measuring total liver TAG levels, which here, only showed a significant effect after the 48 H and 5 day dose regimes. By using a ratio measurement analysis could be performed on plasma samples, greatly simplifying the sample preparation procedure, without the requirement for either calibration curves or an internal standard.  相似文献   

18.
We report the distribution of major and trace element concentrations in epipelagic zooplankton collected in the Northern Gulf of California in August 2003. The Bray–Curtis index defined three element assemblages in zooplankton: (1) major metals, which included only two elements, Na (3.6–17.0%) and Ca (1.0–4.8%). Na had its highest concentrations in the shallow tidally mixed Upper Gulf, where high salinity, temperature, and zooplankton biomass (dominated by copepods) prevailed. Ca showed its highest concentrations south of Ballenas Channel, characterized by tidal mixing and convergence-induced upwelling, indicated by low sea-surface temperature, salinity, and zooplankton biomass; (2) Six biological essential elements, like Fe (80–9,100 mg kg−1) and Zn (20–2,570 mg kg−1), were detected in high concentrations in zooplankton collected near Guaymas Basin, which had high surface temperature and chlorophyll a concentrations. (3) Metals of terrigenous origin, such as Sc (0.01–1.4 mg kg−1) and Th (0.03–2.3 mg kg−1), and redox-sensitive metals, like Co (3–23.8 mg kg−1); this was the assemblage with the largest number of elements (15). Both types of elements of assemblage 3 had maximum concentrations in the cyclonic eddy that dominates the summer circulation in the Northern region. We concluded that sediment resuspension by tidal mixing in the Upper Gulf, upwelling south of Ballenas Channel, and the cyclonic eddy were key oceanographic features that affected the element concentrations of epipelagic zooplankton in the Northern Gulf of California. Oceanographic mechanisms such as these may contribute to element incorporation in marine organisms in other seas.  相似文献   

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20.
In this study, attempts were made to develop a protocol for regeneration of transgenic plants via Agrobacterium tumefaciens-mediated transformation of leaf segments from ‘Valencia’ sweet orange (Citrus sinensis L. Osbeck) using gfp (green fluorescence protein) as a vital marker. Sensitivity of the leaf segments regeneration to kanamycin was evaluated, which showed that 50 mg l−1 was the best among the tested concentrations. In addition, factors affecting the frequency of transient gfp expression were optimized, including leaf age, Agrobacterium concentration, infection time, and co-cultivation period. Adventitious shoots regenerated on medium containing Murashige and Tucker basal medium plus 0.1 mg l−1 α-naphthaleneacetic acid (NAA), 0.5 mg l−1 6-benzyladenine (BA) and 0.5 mg l−1 kinetin (KT). The leaf segments from 3-month-old in vitro seedlings, Agrobacterium concentration at OD600 of 0.6, 10-min immersion, and co-cultivation for 3 days yielded the highest frequency of transient gfp expression, shoots regeneration response and transformation efficiency. By applying these optimized parameters we recovered independent transformed plants at the transformation efficiency of 23.33% on selection medium (MT salts augmented with 0.5 mg l−1 BA, 0.5 mg l−1 KT, 0.1 mg l−1 NAA, 50 mg l−1 kanamycin and 250 mg l−1 cefotaxime). Expression of gfp in the leaf segments and regenerated shoots was confirmed using fluorescence microscope. Polymerase chain reaction (PCR) analysis using gfp and nptII gene-specific primers further confirmed the integration of the transgene in the independent transgenic plants. The transformation methodology described here may pave the way for generating transgenic plants using leaf segments as explants.  相似文献   

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