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51.
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Nguyen Huy Hung Do Ngoc Dai Prabodh Satyal Le Thi Huong Bui Thi Chinh Dinh Quang Hung Thieu Anh Tai William N. Setzer 《化学与生物多样性》2021,18(5):e2100145
Lantana camara is a troublesome invasive plant introduced to many tropical regions, including Southeast Asia. However, the plant does hold promise as a source of essential oils that may be explored for potential use. Fresh water snails such as Pomacea canaliculata, Gyraulus convexiusculus, and Tarebia granifera can be problematic agricultural pests as well as hosts for parasitic worms. Aedes and Culex mosquitoes are notorious vectors of numerous viral pathogens. Control of these vectors is of utmost importance. In this work, the essential oil compositions, molluscicidal, and mosquito larvicidal activities of four collections of L. camara from north-central Vietnam have been investigated. The sesquiterpene-rich L. camara essential oils showed wide variation in their compositions, not only compared to essential oils from other geographical locations (at least six possible chemotypes), but also between the four samples from Vietnam. L. camara essential oils showed molluscicidal activities comparable to the positive control, tea saponin, as well as other botanical agents. The median lethal concentrations (LC50) against the snails were 23.6–40.2 μg/mL (P. canaliculata), 7.9–29.6 μg/mL (G. convexiusculus), and 15.0–29.6 μg/mL (T. granifera). The essential oils showed good mosquito larvicidal activities with 24-h LC50 values of 15.1–29.0 μg/mL, 26.4–53.8 μg/mL, and 20.8–59.3 μg/mL against Ae. aegypti, Ae. albopictus, and Cx. quinquefasciatus, respectively. The essential oils were more toxic to snails and mosquito larvae than they were to the non-target water bug, Diplonychus rusticus (24-h LC50=103.7–162.5 μg/mL). Sesquiterpene components of the essential oils may be acting as acetylcholinesterase (AChE) inhibitors. These results suggest that the invasive plant, L. camara, may be a renewable botanical pesticidal agent. 相似文献
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P. Kathiravan P. K. Dubey S. Goyal B. P. Mishra G. Singh S. M. Deb D. K. Sadana B. K. Joshi R. S. Kataria 《Russian Journal of Genetics》2015,51(8):799-806
In the present study, we report the distribution of true to type and atypical Nili-Ravi buffalo, a vulnerable dairy type riverine breed of North India and its underlying genetic structure. Out of total investigated buffaloes 73.5% had bilateral wall eyes while 5.4% had unilateral wall eyes and 21.1% had no wall eyes. 41.15% of Nili-Ravi buffaloes maintained in the breeding farm were having typical true to the type characteristics (both eyes walled, white markings in forehead, muzzle/chin, all the four legs and tail) while only 28.5% of Nili-Ravi buffaloes were true to the type under field conditions. Genotypic data were generated in four groups of Nili-Ravi buffalo (FMTNR—Typical Nili-Ravi from farm; FMANR—Atypical Nili-Ravi from farm; FDTNR—Typical Nili-Ravi from field; FDANR—Atypical Nili-Ravi from field) at 16 microsatellite loci. Comparative genetic analysis of various groups of Nili-Ravi buffaloes with Murrah revealed significant between group differences with an estimated global F
ST of 0.063. Pair-wise F
ST values ranged from 0.003 (between FDTNR and FDANR) to 0.112 (between FMTNR and FDTNR). Phylogenetic analysis and multi-dimensional scaling revealed clustering of FDTNR and FDANR together while FMTNR and FMANR clustered separately with Murrah in between farm and field Nili-Ravi buffaloes. Based on the results, the paper also proposes three pronged strategy for conservation and sustainable genetic improvement of Nili-Ravi buffalo in India. 相似文献
56.
A fractal analysis is used to model the binding and dissociation kinetics of connective tissue interstitial glucose, adipose tissue interstitial glucose, insulin, and other related analytes on biosensor surfaces. The analysis provides insights into diffusion-limited analyte-receptor reactions occurring on heterogeneous biosensor surfaces. Numerical values obtained for the binding and the dissociation rate coefficients are linked to the degree of heterogeneity or roughness [fractal dimension (Df)] present on the biosensor chip surface. The binding and dissociation rate coefficients are sensitive to the degree of heterogeneity on the surface. For example, for the binding of plasma insulin, as the fractal dimension value increases by a factor of 2.47 from Df1 = 0.6827 to Df2 = 1.6852, the binding rate coefficient increases by a factor of 4.92 from k1 = 1.0232 to k2 = 5.0388. An increase in the degree of heterogeneity on the probe surface leads to an increase in the binding rate coefficient. A dual-fractal analysis is required to fit the binding kinetics in most of the cases presented. A single fractal analysis is adequate to describe the dissociation kinetics. Affinity (ratio of the binding to the dissociation rate coefficient) values are also presented. Interferents for glucose, such as uric acid and ascorbic acid, were also detected by using glucose biosensors based on carbon nanotube (CNT) nanoelectrode ensembles (NEEs) (Lin Y, Lu F, Tu Y, Ren Z. Nano Lett 2004, 4, 191–195). 相似文献
57.
Risal P Cho BH Sylvester KG Kim JC Kim HT Jeong YJ 《In vitro cellular & developmental biology. Animal》2011,47(8):526-534
Hepatocytes are an important research tool used for numerous applications. However, a short life span and a limited capacity
to replicate in vitro limit the usefulness of primary hepatocyte cultures. We have hypothesized that in vivo priming of hepatocyte
could make them more susceptible to growth factors in the medium for continuous proliferation in vitro. Here, a novel approach
used to establish hepatocyte cell lines that included hepatocyte priming in vivo prior to culture with a 3,5-diethoxycarbonyl-1,4-dihydrocollidine
diet was attempted. The cell line grew in a monolayer while maintaining a granular cytoplasm and a round nucleus. Electron
microscopy displayed hepatocyte-like features including mitochondria, glycogen granules, and the presence of bile canaliculi.
This cell line expressed many mature hepatocyte-specific genes including albumin, alpha1-antitrypsin, glucose 6-phosphatase,
and tyrosine aminotransferase. Functional characteristic of hepatocytes like the ability to store glycogen, lipid, and synthesis
of urea is well demonstrated by this cell line. These cells demonstrated anchorage dependent growth properties in soft agar
and did not form tumors after transplantation into nude mice. This cell line can be sustained in culture for more than 100
passages (>1.5 years) without undergoing noticeable morphological changes or transformation. This novel method resulted in
the establishment of an immortal, non-transformed hepatocyte cell line with functional characteristics that may aid research
of cell metabolism, toxicology, and hepatocyte transplantation. 相似文献
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Sharma A Kumar V Jain S Sharma PC 《Journal of enzyme inhibition and medicinal chemistry》2011,26(4):546-552
Starting from capric acid, hydrazone and thiazolidin-4-one derivatives have been synthesized in the present investigation. Decanoic acid hydrazide was reacted appropriately to yield hydrazones, which were then cyclized to yield the corresponding thiazolidin-4-ones. The structures of the newly synthesized compounds were confirmed by analytical and spectral methods. Anti-inflammatory, analgesic, and hydrogen peroxide-scavenging activity of the title compounds were evaluated. Among synthesized compounds, 2-hydroxyphenyl thiazolidinone with 44.90% inhibition of inflammation was the most potent anti-inflammatory agent. Similarly, 4-methoxybenzylidine hydrazide with 64.90% inhibition of writhing was observed to be the most potent analgesic agent of the synthesized compounds. All the synthesized compounds exhibited potent hydrogen peroxide-scavenging activity. 相似文献
60.
Devesh Shukla Ravi Kesari Manish Tiwari Sanjay Dwivedi Rudra Deo Tripathi Pravendra Nath Prabodh Kumar Trivedi 《Protoplasma》2013,250(6):1263-1272
Phytochelatin synthase (PCS) gene encoding key enzyme for heavy metal detoxification and accumulation has been characterised from different sources and used to develop a technology for bioremediation. Past efforts provided limited success and contradictory results. Therefore, functional characterisation of PCS gene from new sources into different target systems is considered as an important task in the area of bioremediation. Earlier, we isolated and functionally characterised PCS gene from an aquatic macrophyte Ceratophyllum demersum L., a metal accumulator aquatic plant. Expression of this gene, CdPCS1, in tobacco enhanced PC synthesis and metal accumulation of transgenic tobacco plants. In the present study, we have expressed CdPCS1 in more diverse systems, Escherichia coli and Arabidopsis, and studied growth and metal accumulation of transgenic organisms. The expression of CdPCS1 in E. coli offered tolerance against cadmium as well as higher accumulation accompanied with PCS1 activity. The expression of CdPCS1 in Arabidopsis showed a significant enhanced accumulation of heavy metal(loid)s in aerial parts without significant difference in growth parameters in comparison to wild-type Arabidopsis plants. Our study suggests that CdPCS1 can be utilised for enhancing bioremediation potential of different organisms using biotechnological approaches. 相似文献