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101.
Veronika Kozlovskaya Yiming Yang Fei Liu Kevin Ingle Aftab Ahmad Ganesh V. Halade Eugenia Kharlampieva 《Molecules (Basel, Switzerland)》2022,27(11)
Limited tissue selectivity and targeting of anticancer therapeutics in systemic administration can produce harmful side effects in the body. Various polymer nano-vehicles have been developed to encapsulate therapeutics and prevent premature drug release. Dually responsive polymeric vesicles (polymersomes) assembled from temperature-/pH-sensitive block copolymers are particularly interesting for the delivery of encapsulated therapeutics to targeted tumors and inflamed tissues. We have previously demonstrated that temperature-responsive poly(N-vinylcaprolactam) (PVCL)-b-poly(dimethylsiloxane) (PDMS)-b-PVCL polymersomes exhibit high loading efficiency of anticancer therapeutics in physiological conditions. However, the in-vivo toxicity of these polymersomes as biocompatible materials has not yet been explored. Nevertheless, developing an advanced therapeutic nanocarrier must provide the knowledge of possible risks from the material’s toxicity to support its future clinical research in humans. Herein, we studied pH-induced degradation of PVCL10-b-PDMS65-b-PVCL10 vesicles in-situ and their dually (pH- and temperature-) responsive release of the anticancer drug, doxorubicin, using NMR, DLS, TEM, and absorbance spectroscopy. The toxic potential of the polymersomes was evaluated in-vivo by intravenous injection (40 mg kg−1 single dose) of PVCL10-PDMS65-PVCL10 vesicles to mice. The sub-acute toxicity study (14 days) included gravimetric, histological, and hematological analyses and provided evidence for good biocompatibility and non-toxicity of the biomaterial. These results show the potential of these vesicles to be used in clinical research. 相似文献
102.
Ruud Peters Ingrid Elbers Anna Undas Eelco Sijtsma Sophie Briffa Pauline Carnell-Morris Agnieszka Siupa Tae-Hyun Yoon Loïc Burr David Schmid Jutta Tentschert Yves Hachenberger Harald Jungnickel Andreas Luch Florian Meier Jovana Kocic Jaeseok Kim Byong Chon Park Barry Hardy Colin Johnston Kerstin Jurkschat Jrg Radnik Vasile-Dan Hodoroaba Iseult Lynch Eugenia Valsami-Jones 《Molecules (Basel, Switzerland)》2022,27(15)
103.
Joana Gonalves ngelo Luís Eugenia Gallardo Ana Paula Duarte 《Molecules (Basel, Switzerland)》2022,27(18)
Ayahuasca is an Amazonian drink, which contains β-carboline alkaloids and N,N-dimethyltryptamine. The aim of this study was to evaluate the healing potential of decoctions of a commercial mixture, four individual plants and four mixtures of two plants used in the ayahuasca preparation. Thus, the cytotoxic potential of the samples was evaluated and a wound-healing assay was performed with a NHDF cell line. Subsequently, a parallel artificial membrane permeability assay was also performed, to verify if any psychoactive compound could be absorbed by skin fibroblasts. The integrity and permeability of the cell layer were also evaluated, using the transepithelial electrical resistance assay and Lucifer yellow permeability assay, respectively. The compounds absorbed by the cell layer were quantified by high-performance liquid chromatography coupled to a diode array detector. The results showed that only one sample showed cytotoxicity and all the others promoted the migration of skin fibroblasts. Additionally, it was also verified that β-carbolynic alkaloids and N,N-dimethyltriptamine were not absorbed by the cell layer, and in general, did not interfere with its permeability and integrity. To the best of our knowledge, this is the first study where ayahuasca’s wound-healing potential was evaluated. 相似文献
104.
105.
Ion Irimescu und Eugenia Chirnoag 《Fresenius' Journal of Analytical Chemistry》1943,125(1-2):32-37
Ohne Zusammenfassung 相似文献
106.
107.
Semigroup Forum - We study properties of eigenvalues of a matrix associated with a randomly chosen partial automorphism of a regular rooted tree. We show that asymptotically, as the level number... 相似文献
108.
Existence and uniqueness of solutions in H1(Δ) of a general class of non-linear functional equations
Eugenia N. Petropoulou 《Journal of Mathematical Analysis and Applications》2003,279(2):451-462
A functional analytic method is used to prove the existence and the uniqueness of a solution in the Banach space H1(Δ) of a general class of non-linear functional equations. This general class includes some specific functional equations studied recently. Our results simplify and improve the existing results for these specific equations. Moreover, for one of them, we give an answer to an open problem. 相似文献
109.
Estimates of convergence rates for rescaled eigenvalues of the stiff Neumann problem for the Laplacian are obtained. The bounds are expressed in terms of the stiffness ratio and properties of the limit spectrum both for low and middle frequency ranges. To cite this article: M. Lobo et al., C. R. Mecanique 331 (2003). 相似文献
110.
Eugenia N. Petropoulou Efstratios E. Tzirtzilakis 《Journal of Mathematical Analysis and Applications》2007,331(1):279-296
A functional-analytic technique was developed in the past for the establishment of unique solutions of ODEs in H2(D) and H1(D) and of difference equations in ?2 and ?1. This technique is based on two isomorphisms between the involved spaces. In this paper, the two isomorphisms are combined in order to find discrete equivalent counterparts of ODEs, so as to obtain eventually the solution of the ODEs under consideration. As an application, the Duffing equation and the Lorenz system are studied. The results are compared with numerical ones obtained using the 4th order Runge-Kutta method. The advantages of the present method are that, it is accurate, the only errors involved are the round-off errors, it does not depend on the grid used and the obtained solution is proved to be unique. 相似文献