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Several neurodegenerative diseases such as Alzeimer's and Parkinson's as well as septic shock and inflammation involve formation of reactive oxygen and nitrogen species that include peroxynitrite (PON). PON can also react with endogenous antioxidants. Therefore, dietary supplementation with antioxidants may help in these diseases. An exogenous antioxidant, vanillin (4-hydroxy-3-methoxybenzaldehyde), used widely as a food flavoring agent, was evaluated for its ability to scavenge PON and inhibit PON-mediated reactions. Nitration of tyrosine by PON was assessed by high-performance liquid chromatography (HPLC). This reaction was inhibited by vanillin. The oxidation of dihydrorhodamine 123 to fluorescent rhodamine 123 was also inhibited by vanillin. The kinetics of reaction between PON and vanillin was studied by stopped-flow technique. The products of this reaction were analyzed by HPLC, and hydroxyvanillin was identified as one of the five products with absorption at 350 nm. These data demonstrate that vanillin effectively scavenges PON in cell-free systems. 相似文献
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Penultimate and last instar larvae of the common citrus swallowtail butterfly, Papilio demoleus L. (Papilionidae: Lepidoptera), were treated with different doses of a novel juvenoid, diofenolan. Several deformities were
observed as a result of topical administration of diofenolan which include delay in larval–larval and larval–pupal ecdysis,
ecdysial failure, mortality, severe reduction in pupation, deformed pupae and complete inhibition of adult emergence. The
juvenoid diofenolan severely hampers the normal growth, development and metamorphosis of P. demoleus and can be incorporated into integrated pest management programs for successful control of this important pest of citrus
all over the world. 相似文献
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Renu Pandey Krishna Kant Dubey Altaf Ahmad Rakshanda Nilofar Rachana Verma Vanita Jain 《Journal of plant nutrition》2015,38(8):1196-1217
Cultivars of Triticum aestivum, T. durum, and Secale cereale were grown at low (2 μM) and sufficient (500 μM) phosphorus (P) under ambient carbon dioxide (380 μmol mol?1; aCO2) and elevated CO2 (700 μmol mol?1, eCO2) to study responses of cereal species in terms of growth and P utilization efficiency (PUE) under P x CO2 interaction. Dry matter accumulation increased under eCO2 with sufficient P. Nevertheless, dry matter accumulated at eCO2 with low-P was similar to that obtained at aCO2 with sufficient P. Leaf area was 43% higher under eCO2 with sufficient P. Significant increase in lateral root density, length and surface area were noted at low-P under eCO2. Phosphorus use efficience (PUE) increased by 59% in response to eCO2 in low-P plants. Thus, eCO2 can partly compensate effect of low-P supply because of improved utilization efficiency. Among cereals, durum wheat was more suitable in terms of PUE under high CO2 and limiting P supply. 相似文献
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ABSTRACT Late leaf spot (LLS), caused by Phaeoisariopsis personata, is a foliar disease of groundnut or peanut (Arachis hypogaea) with high economic and global importance. Antifungal and chitinolytic Bacillus circulans GRS 243 and Serratia marcescens GPS 5, selected among a collection of 393 peanut-associated bacteria, were applied as a prophylactic foliar spray and tested for control of LLS. Chitin-supplemented application of B. circulans GRS 243 and S. marcescens GPS 5 resulted in improved biological control of LLS disease. Supplementation of bacterial cells with 1% (wt/vol) colloidal chitin reduced lesion frequency by 60% compared with application of bacterial cells alone, in the greenhouse. Chitinsupplemented application of GRS 243 and GPS 5 also resulted in improved and stable control of LLS in a repeated field experiment and increased the pod yields by 62 and 75%, respectively, compared with the control. Chitin-supplemented application of GPS 5 was tested in six onfarm trials, and the increase in pod yields was up to 48% in kharif (rainy season). A 55-kDa chitinase was purified from the cell-free culture filtrate of GPS 5 by affinity chromatography and gel filtration. Purified chitinase of S. marcescens GPS 5 (specific activity 120 units) inhibited the in vitro germination of P. personata conidia, lysed the conidia, and effectively controlled LLS in greenhouse tests, indicating the importance of chitinolysis in biological control of LLS disease by GPS 5. 相似文献
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Rawther SS Saseendranath MR Nair GP Tresamol PV Pillai UN Abraham J Senthilkumar TM Nagalakshmy S Nimisha KK 《Tropical animal health and production》2012,44(4):911-914
In the present study efficacy of single intradermal Johnin test, acid fast staining of faecal smear and IS 900 faecal polymerase chain reaction tests was evaluated in 200 goats for detection of Mycobacterium avium subsp paratuberculosis. Two hundred goats comprising 150 goats from an organised farm in Trichur district and 50 goats reared under field condition
at farmers premise from Malappuram district of Kerala state formed the study population. Faecal smear from all the 200 goats
was stained by Ziehl–Neelsen acid fast stain and faecal polymerase chain reaction (PCR) specific for M. avium subsp paratuberculosis (MAP); IS 900 was performed on all samples. All the animals were subjected to single intradermal Johnin test. Out of 200 goats screened
for paratuberculosis, six goats (3%), 11 goats (5.5%) and 42 goats (21%) were found positive by Ziehl–Neelsen acid fast staining
of faecal smear, single intradermal Johnin test and IS 900 PCR respectively. Results of the present study indicate that amplification of IS 900 insertion element was the most specific and sensitive diagnostic detection method. Single intradermal Johnin test and Ziehl–Neelsen
acid fast staining did not show any significant difference. 相似文献