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Jain Priyanka Hussian Samreen Nishad Jyoti Dubey Himanshu Bisht Deepak Singh Sharma Tilak Raj Mondal Tapan Kumar 《Molecular biology reports》2021,48(3):2261-2271
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Mukesh Meena Andleeb Zehra Prashant Swapnil Manish Kumar Dubey Chandra Bali Patel R. S. Upadhyay 《Archives Of Phytopathology And Plant Protection》2017,50(7-8):317-329
Tomato is considered as one of the most important sources of nutrients such as lycopene, β-carotene, flavonoids, ascorbic acid (vitamin C) and hydroxyl-cinnamic acid derivatives. The quality and quantity of nutrients in tomato fruits were decreased during the severe infection of Alternaria alternata. The present study deals with the estimation of lycopene, β-carotene, phenolic and ascorbic acid content in tomato fruits which were infected with A. alternata and its toxins such as tenuazonic acid (TeA), alternariol (AOH) and alternariol monomethyl ether (AME). The lycopene, β-carotene, ascorbic acid and phenolic content were found lowest in pathogen-infected fruits i.e. (0.66 ± 0.03 mg/g), (0.14 ± 0.01 mg/g), (1.89 ± 0.2 mg/g) and (0.58 ± 0.05 mg/g), respectively, followed by toxins-treated samples as compared to the control. The results concluded that A. alternata mostly affects the nutritional values of tomato fruits due to the combined effect of the toxins. 相似文献
15.
Raj Kumar Koiri Surendra Kumar Trigun Santosh Kumar Dubey Santosh Singh Lallan Mishra 《Biometals》2008,21(2):117-126
Metal complex–protein interaction is an evolving concept for determining cellular targets of metallodrugs. Lacatate dehydrogenase
(LDH) is critically implicated in tumor growth and therefore, considered to be an important target protein for anti-tumor
metal complexes. Due to efficient biocompatibility of copper (Cu2+) and zinc (Zn2+), we synthesized CubpyAc2 · H2O (Cu-bpy) and ZnbpyAc2 · H2O (Zn-bpy; where bpy = 2,2′ bipyridine, Ac = CH3COO−) complexes and evaluated their interaction with and modulation of LDH in mouse tissues. The increasing concentration of both
the complexes showed a significant shift in UV–Vis spectra of LDH. The binding constant data (Kc = 1 × 103 M−1 for Cu-bpy and 7 × 106 M−1 for Zn-bpy) suggested that Zn-bpy-LDH interaction is stronger than that of Cu-bpy-LDH. LDH modulating potential of the complexes
were monitored by perfusing the mice tissues with non-toxic doses of Cu-bpy and Zn-bpy followed by activity measurement and
analysis of LDH isozymes on non-denaturing polyacrylamide gel electrophoresis (PAGE). As compared to the control sets, Cu-bpy
caused a significant decline (P < 0.05–0.001) in the activity of LDH in all the tissues studied. However, Zn-bpy showed inhibition of LDH only in liver (P < 0.01), kidney (P < 0.001) and heart (P < 0.01), but with no effect in spleen, brain and skeletal muscle tissues. PAGE analysis suggested that all the five LDH isozymes
are equally sensitive to both the complexes in the respective tissues. The results suggest that Cu- and Zn-bpy are able to
interact with and inhibit LDH, a tumor growth supportive target protein at tissue level. 相似文献
16.
A Gyr Falcon Falco rusticolus population in Northern Sweden (66°N, 17°E) was monitored from 1996 to 2002 in relation to its predator–prey interactions with its main and alternative prey species. Ptarmigan species Lagopus spp., and especially Rock Ptarmigan L. mutus , were the Gyr Falcons' most important prey and constituted more than 90% of the prey biomass. A 21-fold difference in ptarmigan abundance was found across Falcon breeding territories. However, this great variation in prey availability corresponded to only about a 10% shift in Gyr Falcon diet across territories, suggesting that the Falcons were reluctant or unable to compensate for declining ptarmigan availability by using alternative prey categories. Gyr Falcons did not respond functionally to microtine rodent abundance. Their diets were unaffected by a peak in the microtine rodent population cycle when Norwegian Lemmings Lemmus lemmus occurred in high numbers in the study area. Gyr Falcons responded numerically to their prey in two ways. First, there was a reproductive response with a significant relationship between the number of chicks fledged and the number of ptarmigan in the breeding territories. Secondly, although the Gyr Falcons did not utilize microtines as prey, there was a relationship between the microtine rodent abundance and the number of pairs that attempted to breed each year. This could be a result of an indirect community interaction, assuming that other predators switched from ptarmigan to microtines as prey, which could have had a positive effect on the breeding performance of the Gyr Falcons. The Gyr Falcons acted as true specialist predators, and their narrow food niche probably reflected a general lack of suitable alternative prey in the study area. 相似文献
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Dubey JP Alvarado-Esquivel C Liesenfeld O Herrera-Flores RG Ramírez-Sánchez BE González-Herrera A Martínez-García SA Bandini LA Kwok OC 《The Journal of parasitology》2007,93(5):1033-1035
Toxoplasma gondii and Neospora caninum are structurally similar parasites, with many hosts in common. The prevalence of antibodies to T. gondii and N. caninum was determined in sera from dogs from Durango City, Mexico. Using a modified agglutination test, antibodies to T. gondii were found in 52 (51.5%) of the 101 dogs with titers of 1:25 in 27, 1:50 in 11, 1:100 in 5, 1:200 in 4, 1:400 in 2, 1:800 in 2, and 1:3,200 or higher in 1. Antibodies to N. caninum were determined by the indirect immunofluorescent antibody test (IFAT) and the Neospora sp. agglutination test (NAT). Two of the 101 dogs had N. caninum antibodies; these dogs did not have T. gondii antibodies, supporting the specificity of the tests used. The N. caninum antibody titers of the 2 dogs were: 1:400 by IFAT and 1:200 by NAT in 1, and 1:25 by NAT and IFAT in the other. Results indicate that these 2 structurally similar protozoans are antigenically different. 相似文献
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Evidence suggesting that the ARS elements associated with silencers of the yeast mating-type locus HML do not function as chromosomal DNA replication origins. 总被引:20,自引:21,他引:20 下载免费PDF全文
D D Dubey L R Davis S A Greenfeder L Y Ong J G Zhu J R Broach C S Newlon J A Huberman 《Molecular and cellular biology》1991,11(10):5346-5355
20.
Species identification has been the core issue in all approaches of conservation of endangered wild life. In this regard molecular
techniques for species authentication have proved indispensable. A novel multiplex PCR assay for the identification of three
Indian snake species Python morulus, Ptyas mucosus, and Naja naja is successfully demonstrated using 16S rRNA gene. Three reverse primers and a common forward primer were designed to generate
three different size species-specific PCR fragments. Absence of any PCR amplification in non-target species proves the specificity
of the primers. These four primers were combined in a multiplex assay to enable identification of three snake species in a
single reaction. The assay described here shows its utility in identifying unknown snake specimen and in case of samples yielding
low quality DNA. This multiplex PCR technique using novel primers is an unprecedented approach offered for forensic identification
of exhibits originating from three Indian snake species. It is expected that this endeavor will help strengthening conservation
efforts for these species. 相似文献