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1.
Hamycin incorporated into liposomes containing phosphatidylcholine (SPC) and phosphatidic acid (PA) had reduced toxicity and an enhanced antifungal activity in experimental aspergillosis in balb/c mice. Incorporation of cholesterol into liposomes led to a dose dependent decrease in the toxicity of hamycin. The LD50 (mg/kg) of hamycin contained in SPC/cholesterol/PA (molar ratio 4:5:1) liposomes was 2.8 whereas that in SPC/PA liposomes (molar ratio 9:1) was 0.35. Although the free drug had little or no protective effect on the animals, those administered liposomal hamycin at an equivalent dose (0.1 mg/kg) in the absence of cholesterol (SPC/PA; molar ratio 9:1) showed 90% survival after seven days of therapy. On the other hand the presence of cholesterol in the carrier phosphatidic acid liposomes (SPC/cholesterol/PA; molar ratio 4:5:1) at a similar dose (0.1 mg/kg) led to a 60% survival over the same time period. Hamycin incorporation in phosphatidic acid liposomes both in the presence or absence of cholesterol was found to be effective in reducing the fungal load in lung, liver, spleen and kidney. Studies with distribution of hamycin in various tissues by HPLC showed a significant reduction in the concentration of the liposomal drug in circulation as compared to those seem after administration of free drug.  相似文献   
2.
Journal of Chemical Ecology - Many pollinating insects exhibit flower constancy, i.e. they target flower species they have already experienced and fed from. While the insects might profit from...  相似文献   
3.
Devi  Neena  Patel  Sanjay K. S.  Kumar  Pradeep  Singh  Archana  Thakur  Nandita  Lata  Jeevan  Pandey  Deepak  Thakur  Vikram  Chand  Duni 《Catalysis Letters》2022,152(4):944-953
Catalysis Letters - In this study, Rhodococcus pyridinivorans cells containing hyperactive acyltransferase was immobilized on various macromolecules based-polymeric matrices and used to improve...  相似文献   
4.
The present study was carried out to fabricate the food grade vitamin E acetate nanoemulsion using edible mustard oil and to evaluate its improved bioactivities. A food-grade vitamin E acetate nanoemulsion was fabricated using the edible mustard oil and surfactant Tween-80. Flocculation was not observed for 15 days. The nanoemulsion was characterized for droplet morphology and size distribution using atomic force microscope and zetasizer, respectively. We observe a stable nanoemulsion of spherical morphology and a size distribution of 86.45 ± 3.61 nm. Further, the high-performance liquid chromatography method was used to determine the vitamin E acetate concentration and encapsulation efficiency for the stable nanoemulsion. These nanoemulsions showed improved bioactivity, antioxidant, and antimicrobial activity and could be potentially used to increase the shelf life of fruit juice.  相似文献   
5.
Strains bearing the vph2 mutation are defective in vacuolar acidification. The VPH2 gene was isolated from a genomic DNA library by complementation of the zinc-sensitive phenotype of the mutant. Deletion analysis localized the complementing activity to a 1·2 kb DNA fragment. Sequence analysis of this fragment revealed the presence of a single open reading frame that encoded a protein of 215 amino acids. Computer analysis indicated that the protein, which has a predicted molecular mass of 25 286 Daltons, has two distinct membrane-spanning domains. Biochemical studies indicated that strains bearing the vph2 mutation have greatly reduced levels of vacuolar proton pumping and ATPase activity and that the nucleotide binding subunits of the multimeric vacuolar H+-ATPase failed to be correctly targeted to the vacuolar membrane. The vph2 mutant fails to grow on YEP glycerol medium and on media containing 100 mM -CaCl2 or 4 mM -ZnCl2 or buffered to pH 7·5, a phenotype observed in strains carrying deletions in the genes encoding several vacuolar H+-ATPase subunits. The VPH2 gene is identical to the VMA12 gene (T. Stevens and Y. Anraku, personal communication).  相似文献   
6.
In this communication we propose a method to implement an all-optical astable multivibrator using the non-linear material based switches and logic gates. The scheme can operate in real time. The delay time can achieve ps(pico-second). The pulse duration can be made very low and may cross the THz easily by selecting proper material and laser source.  相似文献   
7.
Urban lakes in many places around the world are rapidly becoming vulnerable because of such factors as urbanization, climate change, anthropogenic pollutant inputs, etc. The influence of such forcing factors on lakes hydrology must be correctly recognized and addressed in order to protect them over the long term. Facing similar challenges, Sukhna Lake, an urban lake in northern India, has apparently dried up frequently in the recent past. Numerous hypotheses were subsequently proposed to isolate the possible factors affecting the lake and its water budget, including the potential impacts of land use changes, climate change, anthropogenic activities and other natural processes. Using meteorological data, lake‐catchment information and a hydrologic model, these hypotheses were comprehensively analysed. Relevant data on rainfall, wind, temperature, lake inflows, groundwater, lake physical characteristics, catchment land uses, soil texture, etc., were gathered for the analysis. A temporal trend analysis of factors relevant to these hypotheses was undertaken to identify critical drivers of hydrological changes. A sensitivity analysis also was performed, using the lake water budget, to determine and prioritize the predominant factors affecting the lake, leading to the creation of an annual lake water budget for the period from 1971 to 2013, highlighting the lake inflows and outflows. The lake annual inflow (catchment run‐off) was computed by adopting a rainfall–run‐off model based on the SCS‐curve number. Lacking any anthropogenic water withdrawals, the outflow was quantified by estimating the evaporation loss (using the FAO‐based Penman–Monteith Equation). The results of the present study  indicate that the process of siltation and the construction of check dams in the catchment, rather than urbanization and climate change, were the dominating reasons contributing to changes in the lake hydrology, and affecting the lake most in recent years.  相似文献   
8.
The effect of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) on the bond strength and durability of the resin-dentin interface using a three-step etch-and-rinse and a universal adhesive (UA) system was investigated. Additionally, the effect of dry and wet bonding on the interface created by UA was evaluated. Investigations carried out were scanning electron microscopy (SEM) evaluation, interfacial nanoleakage expression (NE) and micro-tensile bond strength (μ-TBS) testing. Dentin surfaces of sound molars were acid-etched, pretreated with 0.3 M EDC followed by adhesive application and restored with composite incrementally. Resin-dentin beams for μ-TBS testing and resin-dentin slabs for SEM and NE were sectioned. At 24 h, pre-treatment with EDC did not significantly change the μ-TBS and NE of any of the adhesives compared to their respective controls. There is a significant decrease in the μ-TBS and significant increase in NE after 1 yr of storage compared to the 24 h results. UA in dry bonding conditions pretreated with EDC had higher μ-TBS values than its control. Pre-treatment of acid-etched dentin with 0.3 M EDC for 1 min enhanced the bond strength and durability of the resin-dentin interface created by the tested adhesives. Application of UA in a wet bonding technique appeared less effective than dry bonding technique.  相似文献   
9.
Pgt1p encodes a glutathione transporter in Schizosaccharomyces pombe, orthologous to the Saccharomyces cerevisiae glutathione transporter, Hgt1p. Despite high similarity to Hgt1p, Pgt1p failed to display functionality during heterologous expression in S. cerevisiae. In the present study we employed a genetic strategy to investigate the reason behind the non‐functionality of pgt1+ in S. cerevisiae. Functional mutants were isolated after in vitro mutagenesis. Several mutants were obtained and four mutants analysed. Among these, three yielded different point mutations in the N‐terminal region (301–350 bp) of the transporter before the first transmembrane domain, while one mutant contained a deletion of 42 nucleotides within the same region. The mutant pgt1+ proteins not only expressed and localized correctly, but displayed high‐affinity glutathione transport capabilities in S. cerevisae. Comparison of wild‐type pgt1+ with the functional mutants revealed that a loss in protein expression was responsible for lack of functionality of wild‐type pgt1+ in S. cerevisiae. The mRNA levels in wild‐type and mutants were comparable, suggesting that the block was in translation. The formation of a strong stem–loop structure appeared to be responsible for inefficient translation in pgt1+ and disruption of these structures in the mutants was probably permitting translation. This was confirmed by making silent mutations in this region of wild‐type pgt1+, which led to their functionality in S. cerevisiae. This genetic strategy to relieve functional blocks in expression should greatly facilitate the study of these and other transporters from more intractable genetic organisms in a heterologous expression system. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
10.
Reviews the book, Self and identity in modern psychology and Indian thought by Anand C. Paranjpe (see record 1998-08117-000). This book is an exemplary philosophical-psychological achievement, the result of extensive, sophisticated, and enlightened research. Paranjpe analyzes and compares, based on knowledge of the epistemological, ontological, and ethical foundations of psychology in both the West and India, the problem of person, self, and identity. This is a significant book, not only for the field of the history and theory of psychology but also for psychology in general. Paranjpe, who provides a wealth of knowledge unknown to most Western psychologists, demonstrates that the presumption that Western and Indian psychologies are basically incommensurable is wrong. Psychologists who are genuinely concerned with a science that goes beyond the connection of variables, who believe that incorporating a multicultural perspective into psychology will strengthen the discipline, and who talk about globalization but are interested in the generic meaning of this concept, cannot ignore this masterpiece. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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