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51.
The action of estrogen on target organs has been actively studied with the discovery of estrogen receptor (ER) beta. This study was carried out to examine the expression of ERalpha and ERbeta in the uterus and the vagina of immature Sprague-Dawley rats treated with 17-ethinyl estradiol (EE). Twenty days old rats were subcutaneously treated with EE at the doses of 0 (vehicle control), 0.03, 0.3, 1.0, 3.0, and 10.0 microg/kg/day for three consecutive days. The treatment of EE at the doses of 0.3, 1.0, 3.0 and 10.0 microg/kg/day significantly increased the weights of the uterus and vagina of rats (p<0.01) and retained fluid in the uterus of rats. At the high doses of 3.0 and 10.0 microg/kg/day, the treatment of EE caused an increase in the uterine height, hypertrophy, and a decrease in the expression of ERalpha and ERbeta in the uterine luminal and glandular epithelium. The treatment of EE at the doses of 3.0 and 10.0 microg/kg/day also caused cornification and a decrease in the expression of ERalpha and ERbeta in the vaginal epithelium. These results suggest that the EE treatment decrease the expression of ERalpha and ERbeta in the uterus and vagina of immature rats and that may be associated with the morphological changes such as increase in the uterine height, hypertrophy of the uterine epithelium, and cornification of the vagina.  相似文献   
52.
ABSTRACT

The attractiveness of various protein sources of 16 feed ingredients was determined in juvenile rockfish (Sebastes schlegeli) by using reinforced acrylic tank composed of three equally divided rectangular attracting chambers and an acclimatization chamber. Thirty fish were held in the acclimatization chamber at a time and tournament comparison of feed ingredients was applied to evaluate attractiveness. Jack mackerel (JM) (40.0%), sardine (SM) (33.3%), Pollack (PM) (40.0%), shrimp (SHM) (36.7%), mussel meal (40.0%) and oyster (43.3%) meals achieved the highest feeding attractiveness to rockfish in the 1st through 6th preliminary test, respectively. JM (40.0%), SHM (36.7%), squid meal (SQM) (33.3%), SM (40.3%), PM (40.0%) and PM (36.7%) achieved the highest feeding attractiveness to fish in the 7th through 12th preliminary test, respectively. Among the top five feed ingredients showing high attractiveness to rockfish, JM achieved higher attractiveness than PM and SHM in the 1st trial. In the 2nd trial, attractiveness of JM to rockfish was higher than SM and SQM. SM achieved higher attractiveness to rockfish than SQM, but not different from PM throughout the 30-min observation in the 3rd trial. The strongest feeding attractant response of rockfish was observed in JM, followed by SM, SQM, PM, and SHM, in order among various feed ingredients.  相似文献   
53.
Substitution effect of Undaria pinnatifida with citrus peel by‐product (CPB) on growth, body composition and air exposure stressor of abalone was determined. A total of 1,080 abalone were distributed into 18 net cages. Five formulated diets were prepared in triplicate. The CPB0 diet contained 200 g/kg Upinnatifida. The 250, 500, 750 and 1,000 g/kg U. pinnatifida were substituted with the equal amount of CPB, referred to as the CPB250, CPB500, CPB750 and CPB1000 diets, respectively. Finally, dry U. pinnatifida was prepared. Abalone were fed for 16 weeks and then subjected to air exposure stressor for 24 hr. The cumulative mortality of abalone was monitored for the following 4 days after 24‐hr air exposure. Survival, weight gain and specific growth rate (SGR) of abalone fed all formulated diets were greater than those of abalone fed the U. pinnatifida. The greatest weight gain and SGR were achieved in abalone fed the CPB500 diet. The chemical composition of the soft body of abalone was not affected by the experimental diets. Higher cumulative mortality was observed in abalone fed the CPB0 and dry Upinnatifida at 16 hr after 24‐hr air exposure compared to abalone fed all other diets. In conclusion, U. pinnatifida could be completely substituted with CPB in abalone feed.  相似文献   
54.
Cytochrome P450 (CYP) has been shown to confer resistance in numerous terrestrial insects that consume potentially toxic secondary metabolites in plants, but fewer studies have examined the role of critical biotransformation enzymes in allowing marine organisms to consume chemically defended foods. This study examined the expression of CYP1A and CYP2N mRNAs in several butterflyfish species, which can feed on numerous chemically defended soft and hard corals. In addition, the effect of an extract from a soft coral (Sinnularia maxima) on expression of hepatic CYP1A and CYP2 mRNAs was also examined. Fish were fed extracts on days 1, 3 and 5, and expression was examined on day 5. Phylogenetic analyses of the CYP1A cDNA from 12 species of butterflyfish (DNA, amino acid) indicate well-separated groupings according to their feeding strategies. The non-coralline feeding Chaetodon xanthurus exhibited a 7-fold higher basal expression of CYP2N8 relative to the other species studied. Although induction of CYP2N7 expression was observed in C. punctatofasciatus, CYP1A and CYP2N was largely unaffected or diminished by extract treatment in the other species of butterflyfish. These results indicated groupings of feeding strategy with CYP1A phylogeny in Chaetodon, but generally unaltered expression of CYP1A and CYP2N following dietary treatment with an extract from a chemically defended soft coral suggesting an inconclusive role of these isoforms in the detoxification of chemicals in these extracts.  相似文献   
55.
The recombinant β-tubulin of Pseudocohnilembus persalinus was investigated to test whether tubulin could be a suitable antigenic target against scuticociliatosis. The cDNA of P. persalinus β-tubulin has an open reading frame of 1332 bp and had 15 TAA triplets code for glutamine (Q). All 15 TAA/Q triplets of the β-tubulin cDNA were mutated to universal CAA/Q triplets by site-directed mutagenesis and the mutated β-tubulin was expressed in Escherichia coli as a fusion with glutathione S-transferase (GST-BTU). In Western blot analysis, rat sera immunized with recombinant GST-BTU reacted with reduced β-tubulin of P. persalinus. The immunized rat sera showed higher parasiticidal activity than those of control. Ciliates preincubated with heat-inactivated immune sera showed significantly lower proliferation than ciliates preincubated with control sera when exposed to naïve rat sera as a complement source. The present results suggest that the recombinant β-tubulin of scuticociliates may be used as a target antigen for development of vaccine against scuticociliatosis.  相似文献   
56.
In this review, several recently identified biologically active principles of selected botanical dietary supplement ingredients are described, and were isolated using classical phytochemical chromatographic methods, with various spectroscopic procedures used for their isolation and structure elucidation. A central component of such an approach is “activity-guided fractionation” to monitor the compound purification process. In vitro assays germane to cancer chemoprevention were used to facilitate the work performed. Bioactive compounds, including several new substances, were characterized from açai (Euterpe oleracea), baobab (Adansonia digitata), licorice (Glycyrrhiza glabra), mangosteen (Garcinia mangostana), and noni (Morinda citrifolia). Many of these compounds exhibited quite potent biological activity, but tended to be present in their plant of origin only at low concentration levels.  相似文献   
57.
Sang MK  Kim KD 《Phytopathology》2011,101(6):732-740
We investigated direct and indirect effects of compost water extracts (CWEs) from Iljuk-3, Iljuk-7, Shinong-8, and Shinong-9 for the control of anthracnoses caused by Colletotrichum coccodes on pepper and C. orbiculare on cucumber. All tested CWEs significantly (P < 0.05) inhibited in vitro conidial germination and appressorium formation of the fungal pathogens; however, DL-β-amino-n-butyric acid (BABA) failed to inhibit the conidial development of the pathogens. Direct treatments of the CWEs and BABA on pepper and cucumber leaves at 1 and 3 days before or after inoculation significantly (P < 0.05) reduced anthracnose severities; Iljuk-3, Shinong-9, and BABA for pepper and Iljuk-7 for cucumber had more protective activities than curative activities. In addition, root treatment of CWEs suppressed anthracnoses on the plants by the pathogens; however, CWE treatment on lower leaves failed to reduce the diseases on the upper leaves of the plants. The CWE root treatments enhanced not only the expression of the pathogenesis-related (PR) genes CABPR1, CABGLU, CAChi2, CaPR-4, CAPO1, and CaPR-10 in pepper and PR1-1a, PR-2, PR-3, and APOX in cucumber but also the activity of β-1,3-glucanase, chitinase, and peroxidase and the generation of hydrogen peroxide in pepper and cucumber under pathogen-inoculated conditions. However, the CWE treatments failed to induce the plant responses under pathogen-free conditions. These results indicated that the CWEs had direct effects, reducing anthracnoses by C. coccodes on pepper leaves and C. orbiculare on cucumber leaves through protective and curative effects. In addition, CWE root treatments could induce systemic resistance in the primed state against pathogens on plant leaves that enhanced PR gene expression, defense-related enzyme production, and hydrogen peroxide generation rapidly and effectively immediately after pathogen infection. Thus, the CWEs might suppress anthracnoses on leaves of both pepper and cucumber through primed (priming-mediated) systemic resistance.  相似文献   
58.
To determine cypermethrin and permethrin in agricultural products, a competitive enzyme-linked immunosorbent assay (ELISA) method was employed. The matrix interferences were minimized by direct dilution of the extracts. No further cleanup was needed. A minimum matrix effect with a 1:10 dilution of white wine for cypermethrin and a 1:200 dilution of red and white wines, fruits, and vegetables for permethrin was found when phosphate-buffered saline containing 40% methanol was employed as the diluent. Good recoveries of spiked levels were observed. The mean percentage recoveries of cypermethrin spiked in white wine and permethrin spiked in red and white wines were 99.7, 74, and 78%, respectively. The mean percentage recoveries of permethrin spiked in apple, banana, cucumber, lettuce, onion, and peach were 99.2, 105, 70.2, 97.5, 94.4, and 89.4%, respectively. Validation of the ELISA method with permethrin-spiked lettuce and peach was carried out using gas chromatography with mass spectrometry, resulting in a good recovery and correlation.  相似文献   
59.
Tocochromanols are potent lipid-soluble antioxidants and essential nutrients for human health. Genetic engineering techniques were used to develop soybeans with enhanced vitamin E levels, including tocotrienols, which are not found in soybean. The gene encoding rice homogentisate geranylgeranyl transferase (HGGT) was overexpressed in soybeans using seed-specific and constitutive promoters. The association between abundance of vitamin E isomers and antioxidant activity was investigated during seed germination. With the exception of β-tocotrienol, all vitamin E isomers were detected in germinating seeds expressing OsHGGT. The antioxidant properties of germinating seed extracts were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radicals and lipid peroxidation (TBARS). Compared with intact wild-type seeds, transgenic seeds showed increases in radical scavenging of 5.4-17 and 23.2-35.3% in the DPPH and ABTS assays, respectively. Furthermore, the lipid peroxidation levels were 2.0-4.5-fold lower in germinating seeds from transgenic lines than in wild-type seeds. Therefore, it appears that the antioxidant potential of transgenic oil-producing plants such as soybean, sunflower, and corn may be enhanced by overexpressing OsHGGT during seed germination.  相似文献   
60.
The purpose of this study was to survey the distribution patterns of volatile organic compounds (VOCs) and formaldehyde in the various indoor environments using cluster analysis. We investigated VOCs and formaldehyde in subway stations, underground shopping areas, medical centers, maternity recuperation centers, public childcare centers, large stores, funeral homes, and indoor parking lots from June 2005 to May 2006 (9 p.m. to 6 a.m.). The concentration of total volatile compounds (TVOCs) in maternity recuperations was 2,605.7 ??g/m3, which was higher than that stated in the guideline and other chosen facilities. TVOCs in public childcare centers were 1,951.6 ??g/m3, which also exceeded the guideline. Moreover, the concentration of TVOCs in every facility exceeded the guideline of the Ministry of Environment, Korea. In the case of formaldehyde, the mean concentration of 336.5 ??g/m3 found only in public childcare centers exceeded the 120 ??g/m3 stated in the guideline. Finally, by applying cluster analysis, three patterns of the indoor air pollutions were distinguished. In the results of the analysis, concentrations of TVOCs and formaldehyde of cluster 3 were higher than clusters 1 and 2, which were 2,561.4 and 184.9 ??g/m3, respectively.  相似文献   
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