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31.
Microemulsions (MEs) are clear, thermodynamically stable systems. They were used to solubilize drugs and to improve topical drug availability. Salicylic acid (SA) is a keratolytic agent used in topical products with antimicrobial actions. The objective of this work was to prepare and evaluate SA ME systems. Different concentrations of SA were incorporated in an ME base composed of isopropyl myristate, water, and Tween 80: propylene glycol in the ratio of 15:1. Three ME systems were prepared: S2%, S5%, and S10% which contain 2%, 5%, and 10% of SA, respectively. Evaluation by examination under cross-polarizing microscope, measuring of percent transmittance, pH measurement, determination of the specific gravity, assessment of rheological properties, and accelerated stability study were carried out. The data showed that the addition of SA markedly affected the physical properties of the base. All systems were not affected by accelerated stability tests. Stability study for 6 months under ambient conditions was carried out for S10%. No remarkable changes were recorded except a decrease in the viscosity value after 1 month. The results suggested that ME could be a suitable vehicle for topical application of different concentrations of SA.  相似文献   
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Introduced plants may out-compete natives by belowground allelopathic effects on soil communities including the symbionts of native plants. We tested for an allelopathic effect of an introduced crucifer, Raphanus sativus, on a common neighboring legume, Lupinus nanus, on the legume’s rhizobium affiliates, and on the broader soil community. In both field observations and a greenhouse experiment, we found that R. sativus decreased the density of nodules on L. nanus roots. However, in the greenhouse experiment, R. sativus soils only decreased the density of small, likely non-beneficial rhizobium nodules. In the same experiment, R. sativus soils decreased fungivorous nematode abundance, though there was no effect of R. sativus introduction on fungal density. In the greenhouse experiment, R. sativus soils had a net positive effect on L. nanus biomass. One explanation of this effect is that R. sativus introduction might alter the mutualistic/parasitic relationship between L. nanus and its rhizobial associates with a net benefit to L. nanus. Our results suggest that introduced brassicas can quickly alter belowground communities, but that the net effect of this on neighboring plants is not necessarily negative.  相似文献   
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Rice bran oil is known as wonder oil and it is the most important vegetable oil in Asia. Rice bran oil is extracted from bran that is the outer hard layer of rice. It is an emerging category in edible oil with a lot of nutritional properties and health benefits. Rice bran oil is heart-friendly, boosts up immunity, and prevents from other diseases occurring commonly in Pakistan. The current study aimed to stabilize rice bran oil through different probiotic isolates and to assess the nutritional content of rice bran oil after stabilization. The study was aimed to inactivate naturally occurring lipases that can hydrolyze oil into glycerol and free fatty acid which is a serious problem that gives it a rancid taste and smell. Antilipase activity was used to inactivate naturally occurring lipases that are a huge threat to the stabilization process. The fermentation process utilizes antilipase activity without affecting the nutritional value of oil. Lactobacillus strains were used for the stabilization of rice bran oil. Rice bran oil was extracted in the Soxhlet apparatus. The probiotic lab isolates Lactobacillus delbrueckii S2, Lactobacillus casei S5 and Lactobacillus plantarum S13 were applied to it to increase its shelf life and prevent oxidative rancidity. The extraction temperature of rice bran oil was maintained above 40 °C to inhibit lipase activity. Rice bran oil samples were stored at refrigeration temperature to arrest lipase activity. Probiotics maintained acidic pH to keep oil stabilization. Qualitative analysis was done to confirm rice bran oil stabilization. Determination of Free Fatty Acid (FFA) and saponification value confirmed that oxidative rancidity of rice bran oil was controlled by probiotics. FFA count was less than 10% and Saponification Value (SV) was 180. GC analysis was performed to analyze the FFA profile. Gas Chromatography results have shown 3 fatty acids. Statistical analysis has shown non-significant effect on different incubation temperatures of Lactobacillus isolates. Among the biological methods of stabilization, the use of probiotics is a novel concept and recommended for commercial application.  相似文献   
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Pseudopheochromocytoma is a poorly understood, rare cause of severe paroxysmal hypertension that mimics the symptomatology of pheochromocytoma in the absence of biochemical evidence of this tumor. Symptoms such as headache, nausea, sweating, and palpitations during hypertensive episodes have been described. In this paper, we describe previously unreported findings of lateralizing sensorimotor deficits in a patient with pseudopheochromocytoma. These changes presented during a hypertensive episode and were concerning for stroke but were not accompanied by acute radiologic abnormalities. The deficits improved over 1.5 weeks as blood pressure stabilized with beta-blockade. We also review relevant literature on the clinical features, pathophysiology, and management of pseudopheochromocytoma.  相似文献   
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Herceptin failure is a major clinical problem in breast cancer. A subset of breast cancer patients with high HER-2/neu levels eventually experience metastatic disease progression when treated with Herceptin as a single agent. Mechanistic details of development of this aggressive disease are not clear. Therefore, there is a dire need to better understand the mechanisms by which drug resistance develops and to design new combined treatments that benefit patients with aggressive breast cancer and have minimal toxicity. We hypothesized that 3, 3′-diindolylmethane (DIM), a non-toxic agent can be combined with Herceptin to treat breast cancers with high levels of HER-2/neu. Here, we evaluated the effects of Herceptin alone and in combination with DIM on cell viability, apoptosis and clonogenic assays in SKBR3 (HER-2/neu-expressing) and MDA-MB-468 (HER-2/neu negative) breast cancer cells. We found that DIM could enhance the effectiveness of Herceptin by significantly reducing cell viability, which was associated with apoptosis-induction and significant inhibition of colony formation, compared with single agent treatment. These results were consistent with the down-regulation of Akt and NF-kB p65. Mechanistic investigations revealed a significant upregulation of miR-200 and reduction of FoxM1 expression in DIM and Herceptin-treated breast cancer cells. We, therefore, transfected cells with pre-miR-200 or silenced FoxM1 in these cells for understanding the molecular mechanism involved. These results provide experimental evidence, for the first time, that DIM plus Herceptin therapy could be translated to the clinic as a therapeutic modality to improve treatment outcome of patients with breast cancer, particularly for the patients whose tumors express high levels of HER-2/neu.  相似文献   
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Amine oxidase activity has been identified in commercial samples of bovine serum albumin (BSA). Benzylamine, phenylethylamines and to a lesser extent, indoleamines, were found to be substrates. The amine oxidase activity was inhibited by semicarbazide and was virtually absent in electrophoretically purified samples. Kinetic analysis of benzylamine deamination and experiments utilizing mixed substrates indicate that more than one catalytic activity may be involved. The results show that amine deamination should be considered as a potential source of error in experiments employing high concentrations of commercially available BSA preparations. This would be of particular importance for in vitro studies with dopamine since this amine was found to be deaminated at a rapid rate.  相似文献   
40.
We tested whether direct placement of forest floor material (FFM: litter, fibric, humus layers and surface mineral horizons) and sowing of a cover crop (Melilotus officinalis) could facilitate the establishment of native forest understory species at a reclaimed coal mine in Alberta, Canada. FFM was salvaged at two depths (15 and 40 cm) from a recently harvested native aspen forest and immediately placed at the same depths on the reclamation site. Total richness (approximately 61 species in 96 subplots) was similar in each of 3 years post‐placement; total richness for all 3 years combined was 87 including 34 typical boreal forest understory species plus 30 other natives. The deeper treatment reduced cover of all species, native and non‐native species in year 1. In year 3, the deeper treatment still had lower cover of non‐native species but had higher cover of forest understory species in years 2 and 3. The deeper treatment also resulted in lower species richness per plot, but only in year 1. In year 2 (when the biennial clover was at its tall stage), the cover crop treatment was associated with lower cover of non‐native species but did not affect the cover of native forest understory species. Direct placement of FFM can help facilitate establishment of a diverse native boreal forest understory in a reclaimed landscape. Although richness and cover may be initially higher with shallower salvage and placement, deeper salvage may ultimately be better for encouraging establishment of native forest understory species.  相似文献   
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