This study was conducted to get an idea about the distribution of the lymphatic fluid in conjunctiva throughout the body parts. For this purpose, Qdot655 (QD), fluorescence nanoparticles, spread onto the conjunctiva were used on Wistar albino rats. Drainage of QD particles from conjunctiva was followed up via fluorescence images at different hours on body parts such as eye, ears, forearms, hind legs and tails. The first fluorescence signals within the 30th minutes following administration of QD were observed in the nasal region and the anterior extremities. Whereas within 60th minutes following QD spread, fluorescent signals were obtained from the ears, forearms, hind legs and tail of the female and male rats. 相似文献
CEP peptide was synthesized and tested for induction of disease susceptibility using Arabidopsis Col-0. When Colletotrichum tropicale was used as a non-adapted fungal pathogen, the conidia germinated to form hyphal-like structures, which successfully penetrated epidermis, eventually causing disease symptoms. In such case, PEN2-, but not PEN3-dependent resistance was likely suppressed by CEP peptide. Similarly, the CEP peptide-mediated disease susceptibility was also effective to a non-adapted bacterial pathogen. Notably, such induced susceptibility was also evident on Arabidopsis mutants lacking the previously identified receptors, suggesting that the CEP peptide modulates Arabidopsis immunity through an unidentified receptor(s).
Background:Levan or fructan, a polysaccharide of fructose, is widely used in various commercial industries. Levan could be produced by many organisms, including plants and bacteria. The cloning of the gene from Bacillus licheniformis, which expressed levansucrase in Escherichia coli host, was carried out successfully. In the present study, we performed the in vitro production of levan and analyzed its potential application as antibacterial and antioxidant agents. Methods:In vitro levan production catalyzed by heterologous-expressed levansucrase Lsbl-bk1 and Lsbl-bk2 was optimized with BW design. The antibacterial activity of the produced levan was carried out using agar well diffusion method, while its antioxidant activity was tested by free radical scavenging assays. Results:The optimum conditions for levan production were observed at 36 °C and pH 7 in 12% (w/v) sucrose for levansucrase Lsbl-bk1, while the optimum catalysis of levansucrase Lsbl-bk2 was obtained at 32 oC and pH 8 in the same sucrose concentration. The in vitro synthesized levan showed an antibacterial activity within a concentration range of 10-20% (w/v) against Staphylococcus aureus, E. coli, and Pseudomonas aeruginosa. The same levan was also able to inhibit the DPPH radical scavenging activity with the antioxidant strength of 75% compared to ascorbic acid inhibition. Conclusion:Our study, therefore, shows that the optimized heterologous expression of levansucrases encoded by Lsbl-bk1 and Lsbl-bk2 could open the way for industrial levan production as an antibacterial and antioxidant agent. Key Words: Antioxidants, Fructans, In vitro technique, Levan相似文献
Terrestrial laser scanning technology is an advanced active remote sensing ranging method that is well suited for yielding high-resolution scans of the morphology of a tree, which is an indicator of the health of the plant. The Ganoderma boninense fungus causes basal stem rot (BSR), which threatens the oil palm industry in Malaysia. To date, the current practice of inspection in a plantation is conducted every 6 months. Monitoring the progress with a closer gap is required to comprehend if any changes can be seen earlier than 6 months. Therefore, the objectives of this study were to identify the most suitable parameters of the oil palm trees to detect the BSR disease based on temporal laser scanning data and to identify suitable time frames for monitoring the progress of the symptoms of the disease. Terrestrial laser scanning data was used to analyse changes in the crown and frond metrics of oil palm trees with two different scan durations i.e., 2- and 4-months after the first scan. This spatio-temporal data is important in the precision agriculture field for better oil palm management, to understand the disease development for long-term solutions and also to provide a fast response so that appropriate treatment can be given to the palm as early as possible. Statistical analyses, i.e., the Kruskal–Wallis test with α?=?0.05 and the Wilcoxon post-hoc test, were conducted to determine significant differences in the parameters at different points in time. The results show that crown strata number 17 (850 cm from the top) and the crown area were the most suitable parameters to be used. Furthermore, the oil palm trees with BSR can be detected by comparing the 4-month scan or the second 2-month scan. The results have shown that the effect of Ganoderma boninense infection can be differentiated at the later stage. In conclusion, the changes can be measured at 4-months after the first inspection, thus helping to preventing crop losses.
A study was made of the accumulation of aldicarb, ethiofencarb and dimethoate in citrus leaves and fruit; the toxicity of these insecticides to the spirea aphid (Aphis citricola Van der Goot) was also studied. The effectiveness of the treatments was affected mainly by the rate of accumulation of the toxicant in the leaves. At 18 g a.i. per tree, the greatest residues found in the leaves were 106, 12.2 and 1.3 μg 8?1 fresh weight for aldicarb, ethiofencarb and dimethoate, respectively. The concentration in mature leaves was very similar to that in young leaves. The residue levels in the mature fruits were much lower than in the leaves. The main components of the residues in the leaves were aldicarb sulphoxide [2-methyl-2-(methylsulphinyl)- propionaldehyde O-methylcarbamoyloxime], dimethoate, omethoate and ethiofencarb sulphoxide [2-(ethylsulphinylmethyl)phenyl methylcarbamate]. A laboratory study with synthetic diets showed similar toxicity for all three insecticides, whereas in detached leaves, or when taken up by citrus trees, ethiofencarb was the least toxic to the aphids. 相似文献
A bioassay using detached citrus leaves, the petioles of which were immersed in solutions containing insecticides, was used to assess the systemic activity of aldicarb, dimethoate and ethiofencarb on the spirea aphid, Aphis citricola Van der Goot (Homoptera: Aphididae). At identical concentrations in the treatment solutions the order of toxicity to insects of these compounds was aldicarb > dimethoate > ethiofencarb. The toxicity of the residue of aldicarb in the leaves (LC50=2·5 μg/g) resembled that of dimethoate (LC50=1·8 μg/g) and both were more potent than ethiofencarb (LC50=30 μg/g). The amount of aldicarb accumulated in the leaves, 3 days after application, was 25±0·5% of that present in the treatment solution, compared with 4±0·4% of dimethoate and 3±0·3% of ethiofencarb. Thus, the more efficient uptake of aldicarb may be the reason for its high toxicity. When sublethal concentrations of aldicarb incorporated in treatment solutions were taken up by detached leaves, a significant reduction in the pre-reproductive development time, and increased longevity and fecundity were observed. This hormoligosis phenomenon was further emphasized by a considerable increase in aphid weight. This effect seems to be plant mediated, as it was not observed when aldicarb was added to a synthetic diet. Dimethoate showed an effect similar to that of aldicarb, but less pronounced and not statistically significant, whereas ethiofencarb had no such effect. 相似文献
Large shallow earthquakes can induce changes in the fluid pore pressure that are comparable to stress drops on faults. The subsequent redistribution of pore pressure as a result of fluid flow slowly decreases the strength of rock and may result in delayed fracture. The agreement between computed rates of decay and observed rates of aftershock activity suggests that this is an attractive mechanism for aftershockss. 相似文献
The Landers, California, earthquake of 28 June 1992 (magnitude = 7.3) is the latest of six significant earthquakes in the past 60 years whose epicenters and slip directions define a 100-kilometer alignment running approximately N15 degrees W across the central Mojave region. This pattern may indicate a geologically young throughgoing fault that replaces numerous older strike-slip faults by obliquely cutting across them. These older faults, and perhaps also the bend in the San Andreas fault, may be losing their ability to accommodate upper crustal deformation because they have become unfavorably oriented with respect to the regional stress field. 相似文献
ABSTRACT: Expressed sequence tag (EST) analysis is an efficient tool for gene discovery and for profiling gene expression. A cDNA library developed from messenger RNA of the Japanese flounder, Paralichthys olivaceus spleen was constructed by directional cloning, in order to isolate functional genes involved in immunity in fish. A total of 1010 ESTs from the library were sequenced and compared with sequences in the GenBank database. Of the 1010 ESTs, 618 ESTs (61%) were identified as being homologous with known genes from many organisms by BLAST searches, whereas 392 (39%) appeared to be unknown and are likely to represent newly described genes. Of the identified genes, 105 (17%) encoded proteins associated with cell/organism defence and homeostasis. Of these 105 genes, 21 were identified for the first time in Japanese flounder. These included macrophage inflammatory protein (MIP)-3 α, granulin-A, novel immune-type receptor (NITR), interferon regulatory factor (IRF)-10, presenilin-like protein-2, and antizyme inhibitor. A comparison of ESTs derived from spleen, kidney, liver and leukocytes suggested that expression of immune-related genes in different tissues, organs, or cells are different. 相似文献
