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91.
Electrospun cellulose acetate nanofibers: The present status and gamut of biotechnological applications 总被引:1,自引:0,他引:1
Cellulose acetate (CA) has been a material of choice for spectrum of utilities across different domains ranging from high absorbing diapers to membrane filters. Electrospinning has conferred a whole new perspective to polymeric materials including CA in the context of multifarious applications across myriad of niches. In the present review, we try to bring out the recent trend (focused over last five years' progress) of research on electrospun CA fibers of nanoscale regime in the context of developmental strategies of their blends and nanocomposites for advanced applications. In the realm of biotechnology, electrospun CA fibers have found applications in biomolecule immobilization, tissue engineering, bio-sensing, nutraceutical delivery, bioseparation, crop protection, bioremediation and in the development of anti-counterfeiting and pH sensitive material, photocatalytic self-cleaning textile, temperature-adaptable fabric, and antimicrobial mats, amongst others. The present review discusses these diverse applications of electrospun CA nanofibers. 相似文献
92.
93.
Sandhya Sankaranarayanan Margarita de la Llera-Moya Denise Drazul-Schrader Michael C. Phillips Ginny Kellner-Weibel George H. Rothblat 《Journal of lipid research》2013,54(3):671-676
An important mechanism contributing to cell cholesterol efflux is aqueous transfer in which cholesterol diffuses from cells into the aqueous phase and becomes incorporated into an acceptor particle. Some compounds can enhance diffusion by acting as shuttles transferring cholesterol to cholesterol acceptors, which act as cholesterol sinks. We have examined whether particles in serum can enhance cholesterol efflux by acting as shuttles. This task was accomplished by incubating radiolabeled J774 cells with increasing concentrations of lipoprotein-depleted sera (LPDS) or components present in serum as shuttles and a constant amount of LDL, small unilamellar vesicles, or red blood cells (RBC) as sinks. Synergistic efflux was measured as the difference in fractional efflux in excess of that predicted by the addition of the individual efflux values of sink and shuttle alone. Synergistic efflux was obtained when LPDS was incubated with cells and LDL. When different components of LPDS were used as shuttles, albumin produced synergistic efflux, while apoA-I did not. A synergistic effect was also obtained when RBC was used as the sink and albumin as shuttle. The previously observed negative association of albumin with coronary artery disease might be linked to reduced cholesterol shuttling that would occur when serum albumin levels are low. 相似文献
94.
Nivedita P. Khairnar Min-Ho Joe H. S. Misra Sang-Yong Lim Dong-Ho Kim 《Journal of bacteriology》2013,195(12):2880-2886
Deinococcus radiodurans R1 exposed to a lethal dose of cadmium shows differential expression of a large number of genes, including frnE (drfrnE) and some of those involved in DNA repair and oxidative stress tolerance. The drfrnE::nptII mutant of D. radiodurans showed growth similar to that of the wild type, but its tolerance to 10 mM cadmium and 10 mM diamide decreased by ∼15- and ∼3-fold, respectively. These cells also showed nearly 6 times less resistance to gamma radiation at 12 kGy and ∼2-fold-higher sensitivity to 40 mM hydrogen peroxide than the wild type. In trans expression of drFrnE increased cytotoxicity of dithiothreitol (DTT) in the dsbA mutant of Escherichia coli. Recombinant drFrnE showed disulfide isomerase activity and could maintain insulin in its reduced form in the presence of DTT. While an equimolar ratio of wild-type protein could protect malate dehydrogenase completely from thermal denaturation at 42°C, the C22S mutant of drFrnE provided reduced protection to malate dehydrogenase from thermal inactivation. These results suggested that drFrnE is a protein disulfide isomerase in vitro and has a role in oxidative stress tolerance of D. radiodurans possibly by protecting the damaged cellular proteins from inactivation. 相似文献
95.
Sandhya Mishra Ram Sanmukh Upadhyay Chandra Shekhar Nautiyal 《Applied microbiology and biotechnology》2013,97(13):5659-5668
The field of allelopathy is one of the most fascinating but controversial processes in plant ecology that offers an exciting, interdisciplinary, complex, and challenging study. In spite of the established role of soil microbes in plant health, their role has also been consolidated in studies of allelopathy. Moreover, allelopathy can be better understood by incorporating soil microbial ecology that determines the relevance of allelopathy phenomenon. Therefore, while discussing the role of allelochemicals in plant–plant interactions, the dynamic nature of soil microbes should not be overlooked. The occurrence and toxicity of allelochemicals in soil depend on various factors, but the type of microflora in the surroundings plays a crucial role because it can interfere with its allelopathic nature. Such microbes could be of prime importance for biological control management of weeds reducing the cost and ill effects of chemical herbicides. Among microbes, our main focus is on bacteria—as they are dominant among other microbes and are being used for enhancing crop production for decades—and fungi. Hence, to refer to both bacteria and fungi, we have used the term microbes. This review discusses the beneficial role of microbes in reducing the allelopathic effects of weeds. The review is mainly focused on various functions of bacteria in (1) reducing allelopathic inhibition caused by weeds to reduce crop yield loss, (2) building inherent defense capacity in plants against allelopathic weed, and (3) deciphering beneficial rhizospheric process such as chemotaxis/biofilm, degradation of toxic allelochemicals, and induced gene expression. 相似文献
96.
Manish Singh Ashima Singh Somanath Kundu Sandhya Bansal Avinash Bajaj 《生物化学与生物物理学报:生物膜》2013,1828(8):1926-1937
We synthesized four cationic bile acid based facial amphiphiles featuring trimethyl ammonium head groups. We evaluated the role of these amphiphiles for cytotoxic activities against colon cancer cells and their membrane interactions by varying charge, hydration and hydrophobicity. The singly charged cationic Lithocholic acid based amphiphile (LCA-TMA1) is most cytotoxic, whereas the triply charged cationic Cholic acid based amphiphile (CA-TMA3) is least cytotoxic. Light microscopy and Annexin-FITC assay revealed that these facial amphiphiles caused late apoptosis. In addition, we studied the interactions of these amphiphiles with model membrane systems by Prodan-based hydration, DPH-based anisotropy, and differential scanning calorimetry. LCA-TMA1 is most hydrophobic with a hard charge causing efficient dehydration and maximum perturbations of membranes thereby facilitating translocation and high cytotoxicity against colon cancer cells. In contrast, the highly hydrated and multiple charged CA-TMA3 caused least membrane perturbations leading to low translocation and less cytotoxicity. As expected, Chenodeoxycholic acid and Deoxycholic acid based amphiphiles (CDCA-TMA2, DCA-TMA2) featuring two charged head groups showed intermediate behavior. Thus, we deciphered that charge, hydration, and hydrophobicity of these amphiphiles govern membrane interactions, translocation, and resulting cytoxicity against colon cancer cells. 相似文献
97.
Rama Misra U. K. Misra T. A. Venkitasubramanian 《Bioscience, biotechnology, and biochemistry》2013,77(9):1657-1660
A significant increase in adrenal weight, total lipids, cholesterol phospholipids and glycerides (mono-and triglycerides) was observed in rats fed millet at 5, 10 and 15 % protein levels respectively for a period of six weeks as compared to rats fed casein at 10 per cent level. Increases in cholesterol were in both its free and esterified fraction. Adrenal phosphatidyl etha-nolamine was increased in all millet fed rats whereas phosphatidyl choline increased in M–15 % and decreased in M–5 % groups. Other phospholipid fractions viz. monophosphatidyl inositol, lysophosphatidyl ethanolamine, sphingomyeline, phosphatidic acid and polyglycerophosphatide also showed significant alterations in rats fed millet protein as compared to control. Incorporation of acetate–l–14C into adrenal lipids was lower and that of glucose–U–14C, palmitate–l–14C and NaH232PO4 was higher than the control. 相似文献
98.
Pathophysiology of white-nose syndrome in bats: a mechanistic model linking wing damage to mortality
Lisa Warnecke James M. Turner Trent K. Bollinger Vikram Misra Paul M. Cryan David S. Blehert Gudrun Wibbelt Craig K. R. Willis 《Biology letters》2013,9(4)
White-nose syndrome is devastating North American bat populations but we lack basic information on disease mechanisms. Altered blood physiology owing to epidermal invasion by the fungal pathogen Geomyces destructans (Gd) has been hypothesized as a cause of disrupted torpor patterns of affected hibernating bats, leading to mortality. Here, we present data on blood electrolyte concentration, haematology and acid–base balance of hibernating little brown bats, Myotis lucifugus, following experimental inoculation with Gd. Compared with controls, infected bats showed electrolyte depletion (i.e. lower plasma sodium), changes in haematology (i.e. increased haematocrit and decreased glucose) and disrupted acid–base balance (i.e. lower CO2 partial pressure and bicarbonate). These findings indicate hypotonic dehydration, hypovolaemia and metabolic acidosis. We propose a mechanistic model linking tissue damage to altered homeostasis and morbidity/mortality. 相似文献
99.
Manoj K. Mishra Pankaj Chaturvedi Ruchi Singh Gaurav Singh Lokendra K. Sharma Vibha Pandey Nishi Kumari Pratibha Misra 《PloS one》2013,8(4)