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91.
92.
Short AntiMicrobial Peptides (SAMPs) as a class of extraordinary promising therapeutic agents 总被引:1,自引:0,他引:1 下载免费PDF全文
Suhas Ramesh Thavendran Govender Hendrik G. Kruger Beatriz G. de la Torre Fernando Albericio 《Journal of peptide science》2016,22(7):438-451
The emergence of multidrug resistant bacteria has a direct impact on global public health because of the reduced potency of existing antibiotics against pathogens. Hence, there is a pressing need for new drugs with different modes of action that can kill microorganisms. Antimicrobial peptides (AMPs) can be regarded as an alternative tool for this purpose because they are proven to have therapeutic effects with broad‐spectrum activities. There are some hurdles in using AMPs as clinical candidates such as toxicity, lack of stability and high budgets required for manufacturing. This can be overcome by developing shorter and more easily accessible AMPs, the so‐called S hort A nti M icrobial P eptides (SAMPs) that contain between two and ten amino acid residues. These are emerging as an attractive class of therapeutic agents with high potential for clinical use and possessing multifunctional activities. In this review we attempted to compile those SAMPs that have exhibited biological properties which are believed to hold promise for the future. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
93.
Venkateswaran Ganesan Goutam Ulgekar Anandhi Ramalingam Souvik Sen Sharma Nirmalya Ganguli Subeer S. Majumdar 《Cell biochemistry and function》2024,42(2):e3982
Bone Morphogenetic Protein 2 (BMP2), a member of the Transforming Growth Factor-β (TGF-β) super family of proteins and is instrumental in the repair of fractures. The synthesis of BMP2 involves extensive post-translational processing and several studies have demonstrated the abysmally low production of rhBMP2 in eukaryotic systems, which may be due to the short half-life of the bioactive protein. Consequently, production costs of rhBMP2 are quite high, limiting its availability to the general populace. Therefore, there is an urgent need to identify better in-vitro systems for large scale production of rhBMP2. In the present study, we have carried out a comparative analysis of rhBMP2 production by the conventionally used Chinese Hamster ovarian cells (CHO) and goat mammary epithelial cells (GMEC), upon transfection with appropriate construct. Udder gland cells are highly secretory, and we reasoned that such cells may serve as a better in-vitro model for large scale production of rhBMP2. Our results indicated that the synthesis and secretion of bioactive rhBMP2 by goat mammary epithelial cells was significantly higher as compared to that by CHO-K1 cells. Our results provide strong evidence that GMECs may serve as a better alternative to other mammalian cells used for therapeutic protein production. 相似文献
94.
Magnetic core shell nanoparticles are composed of a highly magnetic core material surrounded by a thin shell of desired drug, polymer or metal oxide. These magnetic core shell nanoparticles have a wide range of applications in biomedical research, more specifically in tissue imaging, drug delivery and therapeutics. The present review discusses the up-to-date knowledge on the various procedures for synthesis of magnetic core shell nanoparticles along with their applications in cancer imaging, drug delivery and hyperthermia or cancer therapeutics. Literature in this area shows that magnetic core shell nanoparticle-based imaging, drug targeting and therapy through hyperthermia can potentially be a powerful tool for the advanced diagnosis and treatment of various cancers. 相似文献
95.
A synthetic procedure for the encapsulation of cadmium selenide (CdSe) nanoparticles in a sago starch matrix is introduced. The nanocomposite was investigated using structural, spectroscopic, and thermal methods. TEM micrographs of the nanocomposite showed spherical CdSe particles of 4-5 nm in size coated with a biopolymer layer. The absorption edges of both the aqueous solution and the thin film of the CdSe-starch nanocomposite were shifted toward lower wavelengths in comparison to the value of the bulk semiconductor. Infrared measurements revealed that the interaction of CdSe nanoparticles and starch chains takes place via OH groups. Although the onset of the temperature of decomposition of CdSe-starch nanocomposite is lower than that of the pure matrix, thermogravimetric analysis also showed that introduction of CdSe nanoparticles significantly reduced starch degradation rate leading to high residual mass at the end of the degradation process. 相似文献
96.
Treatment of NaO2CCHC(Me)Fc with cadmium acetate and iron(II) sulfate in the presence of 2,2′-bipy yielded [Cd2Fe(μ-O2CCHC(Me)Fc)2(μ2-O2CCHC(Me)Fc)2(μ2-η2-O2CCHC(Me)Fc)2(2,2′-bipy)2] · 2H2O (1); while from NaO2CC6H4{C(O)Fc-o}, cadmium acetate, and pbbm the product was {[Cd(η2-O2CC6H4{C(O)Fc-o})2(pbbm)] · 0.5H2O}n (2) [Fc = (η5-C5H5)Fe(C5H4-η5); 2,2′-bipy = 2,2′-bipyridyl; pbbm = 1,1′-(1,5-pentamethylene)bis-1H-benzimidazole]. Compounds 1 and 2 have been characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction. In centro-symmetric crystalline 1, the Fe and the two flanking atoms are six-coordinate; the three carboxylato ligands between the Fe and a Cd atom have different coordination modes. Crystalline 2 consists of an infinite polymeric chain, in which adjacent [Cd(η2-O2CC6H4{C(O)Fc-o})2] units are linked by pbbm ligands; thus each Cd atom is six-coordinate. Some electrochemical properties of the two complexes are reported. 相似文献
97.
The attractive and spacing interaction between pairs of filaments via cross-linkers, e.g. myosin oligomers connecting actin
filaments, is modeled by global integral kernels for negative binding energies between two intersecting stiff and long rods
in a (projected) two-dimensional situation, for simplicity. Whereas maxima of the global energy functional represent intersection
angles of ‘minimal contact’ between the filaments, minima are approached for energy values tending to −∞, representing the
two degenerate states of parallel and anti-parallel filament alignment. Standard differential equations of negative gradient
flow for such energy functionals show convergence of solutions to one of these degenerate equilibria in finite time, thus
called ‘super-stable’ states. By considering energy variations under virtual rotation or translation of one filament with
respect to the other, integral kernels for the resulting local forces parallel and orthogonal to the filament are obtained.
For the special modeling situation that these variations only activate ‘spring forces’ in direction of the cross-links, explicit
formulas for total torque and translational forces are given and calculated for typical examples. Again, the two degenerate
alignment states are locally ‘super-stable’ equilibria of the assumed over-damped dynamics, but also other stable states of
orthogonal arrangement and different asymptotic behavior can occur. These phenomena become apparent if stochastic perturbations
of the local force kernels are implemented as additive Gaussian noise induced by the cross-link binding process with appropriate
scaling. Then global filament dynamics is described by a certain type of degenerate stochastic differential equations yielding
asymptotic stationary processes around the alignment states, which have generalized, namely bimodal Gaussian distributions.
Moreover, stochastic simulations reveal characteristic sliding behavior as it is observed for myosin-mediated interaction
between actin filaments. Finally, the forgoing explicit and asymptotic analysis as well as numerical simulations are extended
to the more realistic modeling situation with filaments of finite length.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
98.
The capability of human pluripotent stem cells(h PSCs) to differentiate into a variety of cells in the human body holds great promise for regenerative medicine. Many substrates exist on which h PSCs can be self-renewed, maintained and expanded to further the goal of clinical application of stem cells. In this review, we highlight numerous extracellular matrix proteins, peptide and polymer based substrates, scaffolds and hydrogels that have been pioneered. We discuss their benefits and shortcomings and offer future directions as well as emphasize commercially available synthetic peptidesas a type of substrate that can bring the benefits of regenerative medicine to clinical settings. 相似文献
99.
100.
Quantification of protein concentration by the Bradford method in the presence of pharmaceutical polymers 总被引:1,自引:0,他引:1
We investigated how the Bradford assay for measurements of protein released from a drug formulation may be affected by a concomitant release of a pharmaceutical polymer used to formulate the protein delivery device. The main result is that polymer-caused perturbations of the Coomassie dye absorbance at the Bradford monitoring wavelength (595 nm) can be identified and corrected by recording absorption spectra in the region of 350–850 mm. The pharmaceutical polymers Carbopol and chitosan illustrate two potential types of perturbations in the Bradford assay, whereas the third polymer, hydroxypropylmethylcellulose (HPMC), acts as a nonperturbing control. Carbopol increases the apparent absorbance at 595 nm because the polymer aggregates at the low pH of the Bradford protocol, causing a turbidity contribution that can be corrected quantitatively at 595 nm by measuring the sample absorbance at 850 nm outside the dye absorption band. Chitosan is a cationic polymer under Bradford conditions and interacts directly with the anionic Coomassie dye and perturbs its absorption spectrum, including 595 nm. In this case, the Bradford method remains useful if the polymer concentration is known but should be used with caution in release studies where the polymer concentration may vary and needs to be measured independently. 相似文献