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Jäger A, Jäger E, Syrová Z, Mazel T, Kováčik L, Raška I, Höcherl A, Kučka J, Konefal R, Humajova J, Poučková P, Štěpánek P, Hrubý M. Poly(ethylene oxide monomethyl ether)- block-poly(propylene succinate) Nanoparticles: Synthesis and Characterization, Enzymatic and Cellular Degradation, Micellar Solubilization of Paclitaxel, and in Vitro and in Vivo Evaluation. Biomacromolecules 2018; 19:2443-2458. [PMID: 29601729 DOI: 10.1021/acs.biomac.8b00048] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Polyester-based nanostructures are widely studied as drug-delivery systems due to their biocompatibility and biodegradability. They are already used in the clinic. In this work, we describe a new and simple biodegradable and biocompatible system as the Food and Drug Administration approved polyesters (poly-ε-caprolactone, polylactic acid, and poly(lactic- co-glycolic acid)) for the delivery of the anticancer drug paclitaxel (PTX) as a model drug. A hydrophobic polyester, poly(propylene succinate) (PPS), was prepared from a nontoxic alcohol (propylene glycol) and monomer from the Krebs's cycle (succinic acid) in two steps via esterification and melt polycondensation. Furthermore, their amphiphilic block copolyester, poly(ethylene oxide monomethyl ether)- block-poly(propylene succinate) (mPEO- b-PPS), was prepared by three steps via esterification followed by melt polycondensation and the addition of mPEO to the PPS macromolecules. Analysis of the in vitro cellular behavior of the prepared nanoparticle carriers (NPs) (enzymatic degradation, uptake, localization, and fluorescence resonance energy-transfer pair degradation studies) was performed by fluorescence studies. PTX was loaded to the NPs of variable sizes (30, 70, and 150 nm), and their in vitro release was evaluated in different cell models and compared with commercial PTX formulations. The mPEO- b-PPS copolymer analysis displays glass transition temperature < body temperature < melting temperature, lower toxicity (including the toxicity of their degradation products), drug solubilization efficacy, stability against spontaneous hydrolysis during transport in bloodstream, and simultaneous enzymatic degradability after uptake into the cells. The detailed cytotoxicity in vitro and in vivo tumor efficacy studies have shown the superior efficacy of the NPs compared with PTX and PTX commercial formulations.
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Jäger E, Niggli E, Van der Veen AH. A hydrated barium-strontium pyrochlore in a biotite rock from Panda Hill, Tanganyika. ACTA ACUST UNITED AC 2018. [DOI: 10.1180/minmag.1959.032.244.03] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
SummaryA hydrated barium-strontium pyrochlore with only subordinate amounts of Ca and Na has been found in a weathered biotite rock (contact-rock of a carbonatite) from Panda Hill, Tanganyika, as small euhedral yellowish-grey cubic crystals (showing the combination of the octahedron and the cube) in a rock containing euhedral biotite, some orthoclase, and several other minerals. Hydrated Ba-Sr pyrochlore is isotropic, the refractive index varies from 2·07 to 2·10. The reflectivity (vertical illumination) is 13·2 %. H. Poor {111} cleavage. The pyrochlore structure (space-group O7h–Fd3m) and the unit-cell dimensions (a 10·562 Å.) are derived from X-ray powder and Weissenberg photographs. The calculated specific gravity is 4·01 (observed, 4·00 on dried material). Chemical analysis gives BaO 12·5, SrO 6·4, Na2O 0·28, K2O 0·25, CaO 1·35, rare earths (mainly Ce2O3) 2, ThO2 0·6, FeO 0·45, TiO2 3·9, Nb2O5 67·0, Ta2O5 0·22, H2O+ 4·0, other constituents 2·21, total 101·16. After deduction for impurities the following formula resulted: (Ba0·30Sr0·22Ca0·05Ce0·04Na0·03Fe0·02K0·01Th0·01)(Nb1·83Ta0·004Ti0·17)O5·61(H2O)0·80.The ideal formula for pyrochlore is A2B2O6(F,OH). In the mineral described only a third of the A-positions are occupied by Ba, Sr, etc. Infra-red spectrophotometry does not indicate hydroxyl-groups. When the mineral is treated with TINO3 solution the intensities of the X-ray diffraction lines 333/511, and 444 are changed; hydrated Ba-Sr pyrochlore shows a certain exchange-capacity.The name pandaite, from Panda Hill, is proposed for the new mineral.
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de Castro CE, Ribeiro CAS, Alavarse AC, Albuquerque LJC, da Silva MCC, Jäger E, Surman F, Schmidt V, Giacomelli C, Giacomelli FC. Nanoparticle-Cell Interactions: Surface Chemistry Effects on the Cellular Uptake of Biocompatible Block Copolymer Assemblies. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:2180-2188. [PMID: 29338258 DOI: 10.1021/acs.langmuir.7b04040] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The development of nanovehicles for intracellular drug delivery is strongly bound to the understating and control of nanoparticles cellular uptake process, which in turn is governed by surface chemistry. In this study, we explored the synthesis, characterization, and cellular uptake of block copolymer assemblies consisting of a pH-responsive poly[2-(diisopropylamino)ethyl methacrylate] (PDPA) core stabilized by three different biocompatible hydrophilic shells (a zwitterionic type poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) layer, a highly hydrated poly(ethylene oxide) (PEO) layer with stealth effect, and an also proven nontoxic and nonimmunogenic poly(N-(2-hydroxypropyl)methacrylamide) (PHPMA) layer). All particles had a spherical core-shell structure. The largest particles with the thickest hydrophilic stabilizing shell obtained from PMPC40-b-PDPA70 were internalized to a higher level than those smaller in size and stabilized by PEO or PHPMA and produced from PEO122-b-PDPA43 or PHPMA64-b-PDPA72, respectively. Such a behavior was confirmed among different cell lines, with assemblies being internalized to a higher degree in cancer (HeLa) as compared to healthy (Telo-RF) cells. This fact was mainly attributed to the stronger binding of PMPC to cell membranes. Therefore, cellular uptake of nanoparticles at the sub-100 nm size range may be chiefly governed by the chemical nature of the stabilizing layer rather than particles size and/or shell thickness.
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Jäger A, Jäger E, Giacomelli FC, Nallet F, Steinhart M, Putaux JL, Konefał R, Spěváček J, Ulbrich K, Štěpánek P. Structural changes on polymeric nanoparticles induced by hydrophobic drug entrapment. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2017.10.059] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Höcherl A, Jäger E, Jäger A, Hrubý M, Konefał R, Janoušková O, Spěváček J, Jiang Y, Schmidt PW, Lodge TP, Štěpánek P. One-pot synthesis of reactive oxygen species (ROS)-self-immolative polyoxalate prodrug nanoparticles for hormone dependent cancer therapy with minimized side effects. Polym Chem 2017. [DOI: 10.1039/c7py00270j] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
One-pot synthesis of ROS-self-immolative polyoxalate prodrug NPs for cancer therapy.
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Eichler R, Asai M, Brand H, Chiera N, Di Nitto A, Dressler R, Düllmann C, Even J, Fangli F, Goetz M, Haba H, Hartmann W, Jäger E, Kaji D, Kanaya J, Kaneya Y, Khuyagbaatar J, Kindler B, Komori Y, Kraus B, Kratz J, Krier J, Kudou Y, Kurz N, Miyashita S, Morimoto K, Morita K, Murakami M, Nagame Y, Ooe K, Piguet D, Sato N, Sato T, Steiner J, Steinegger P, Sumita T, Takeyama M, Tanaka K, Tomitsuka T, Toyoshima A, Tsukada K, Türler A, Usoltsev I, Wakabayashi Y, Wang Y, Wiehl N, Wittwer Y, Yakushev A, Yamaki S, Yano S, Yamaki S, Qin Z. Complex chemistry with complex compounds. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201613107005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Khuyagbaatar J, Yakushev A, Düllmann C, Ackermann D, Andersson LL, Block M, Brand H, Even J, Forsberg U, Hartmann W, Herzberg RD, Heßberger F, Hoffmann J, Hübner A, Jäger E, Jeppsson J, Kindler B, Kratz J, Krier J, Kurz N, Lommel B, Maiti M, Minami S, Rudolph D, Runke J, Sarmiento L, Schädel M, Schausten B, Steiner J, Heidenreich TTD, Uusitalo J, Wiehl N, Yakusheva V. Fission in the landscape of heaviest elements: Some recent examples. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201613103003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Geissler K, Jäger E, Barna A, Alendar T, Ljubuncic E, Sliwa T, Valent P. Chronic myelomonocytic leukemia patients with RAS pathway mutations show high in vitro myeloid colony formation in the absence of exogenous growth factors. Leukemia 2016; 30:2280-2281. [PMID: 27585952 PMCID: PMC5097063 DOI: 10.1038/leu.2016.235] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Jäger E, Höcherl A, Janoušková O, Jäger A, Hrubý M, Konefał R, Netopilik M, Pánek J, Šlouf M, Ulbrich K, Štěpánek P. Fluorescent boronate-based polymer nanoparticles with reactive oxygen species (ROS)-triggered cargo release for drug-delivery applications. NANOSCALE 2016; 8:6958-6963. [PMID: 26961769 DOI: 10.1039/c6nr00791k] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A new drug-delivery system of polymer nanoparticles (NPs) bearing pinacol-type boronic ester and alkyne moieties displaying triggered self-immolative polymer degradation in the presence of reactive oxygen species (ROS) with the capability of cellular imaging is presented. The NPs specifically release their drug cargo under concentrations of ROS that are commonly found in the intracellular environment of certain tumors and of inflamed tissues and exhibit significant cytotoxicity to cancer cells compared to their non-ROS-responsive counterparts.
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Albuquerque LJC, Annes K, Milazzotto MP, Mattei B, Riske KA, Jäger E, Pánek J, Štěpánek P, Kapusta P, Muraro PIR, De Freitas AGO, Schmidt V, Giacomelli C, Bonvent JJ, Giacomelli FC. Efficient Condensation of DNA into Environmentally Responsive Polyplexes Produced from Block Catiomers Carrying Amine or Diamine Groups. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:577-586. [PMID: 26677726 DOI: 10.1021/acs.langmuir.5b04080] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The intracellular delivery of nucleic acids requires a vector system as they cannot diffuse across lipid membranes. Although polymeric transfecting agents have been extensively investigated, none of the proposed gene delivery vehicles fulfill all of the requirements needed for an effective therapy, namely, the ability to bind and compact DNA into polyplexes, stability in the serum environment, endosome-disrupting capacity, efficient intracellular DNA release, and low toxicity. The challenges are mainly attributed to conflicting properties such as stability vs efficient DNA release and toxicity vs efficient endosome-disrupting capacity. Accordingly, investigations aimed at safe and efficient therapies are still essential to achieving gene therapy clinical success. Taking into account the mentioned issues, herein we have evaluated the DNA condensation ability of poly(ethylene oxide)113-b-poly[2-(diisopropylamino)ethyl methacrylate]50 (PEO113-b-PDPA50), poly(ethylene oxide)113-b-poly[2-(diethylamino)ethyl methacrylate]50 (PEO113-b-PDEA50), poly[oligo(ethylene glycol)methyl ether methacrylate]70-b-poly[oligo(ethylene glycol)methyl ether methacrylate10-co-2-(diethylamino)ethyl methacrylate47-co-2-(diisopropylamino)ethyl methacrylate47] (POEGMA70-b-P(OEGMA10-co-DEA47-co-DPA47), and poly[oligo(ethylene glycol)methyl ether methacrylate]70-b-poly{oligo(ethylene glycol)methyl ether methacrylate10-co-2-methylacrylic acid 2-[(2-(dimethylamino)ethyl)methylamino]ethyl ester44} (POEGMA70-b-P(OEGMA10-co-DAMA44). Block copolymers PEO113-b-PDEA50 and POEGMA70-b-P(OEGMA10-co-DEA47-co-DPA47) were evidenced to properly condense DNA into particles with a desirable size for cellular uptake via endocytic pathways (R(H) ≈ 65-85 nm). The structure of the polyplexes was characterized in detail by scattering techniques and atomic force microscopy. The isothermal titration calorimetric data revealed that the polymer/DNA binding is endothermic; therefore, the process in entropically driven. The combination of results supports that POEGMA70-b-P(OEGMA10-co-DEA47-co-DPA47) condenses DNA more efficiently and with higher thermodynamic outputs than does PEO113-b-PDEA50. Finally, circular dichroism spectroscopy indicated that the conformation of DNA remained the same after complexation and that the polyplexes are very stable in the serum environment.
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Khuyagbaatar J, Yakushev A, Düllmann CE, Ackermann D, Andersson LL, Block M, Brand H, Cox DM, Even J, Forsberg U, Golubev P, Hartmann W, Herzberg RD, Heßberger FP, Hoffmann J, Hübner A, Jäger E, Jeppsson J, Kindler B, Kratz JV, Krier J, Kurz N, Lommel B, Maiti M, Minami S, Mistry AK, Mrosek CM, Pysmenetska I, Rudolph D, Sarmiento LG, Schaffner H, Schädel M, Schausten B, Steiner J, De Heidenreich TT, Uusitalo J, Wegrzecki M, Wiehl N, Yakusheva V. New Short-Lived Isotope ^{221}U and the Mass Surface Near N=126. PHYSICAL REVIEW LETTERS 2015; 115:242502. [PMID: 26705628 DOI: 10.1103/physrevlett.115.242502] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Indexed: 06/05/2023]
Abstract
Two short-lived isotopes ^{221}U and ^{222}U were produced as evaporation residues in the fusion reaction ^{50}Ti+^{176}Yb at the gas-filled recoil separator TASCA. An α decay with an energy of E_{α}=9.31(5) MeV and half-life T_{1/2}=4.7(7) μs was attributed to ^{222}U. The new isotope ^{221}U was identified in α-decay chains starting with E_{α}=9.71(5) MeV and T_{1/2}=0.66(14) μs leading to known daughters. Synthesis and detection of these unstable heavy nuclei and their descendants were achieved thanks to a fast data readout system. The evolution of the N=126 shell closure and its influence on the stability of uranium isotopes are discussed within the framework of α-decay reduced width.
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Burrer A, Findeisen P, Jäger E, Ghebremedhin B, Grundt A, Ahmad-Nejad P, Miethke T, Neumaier M. Rapid detection of cefotaxime-resistant Escherichia coli by LC–MS. Int J Med Microbiol 2015; 305:860-4. [DOI: 10.1016/j.ijmm.2015.08.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 08/08/2015] [Accepted: 08/16/2015] [Indexed: 11/25/2022] Open
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Jäger E, Giacomelli FC. Soft matter assemblies as nanomedicine platforms for cancer chemotherapy: a journey from market products towards novel approaches. Curr Top Med Chem 2015; 15:328-44. [PMID: 25633209 DOI: 10.2174/1568026615666150130152300] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 11/30/2014] [Accepted: 12/05/2014] [Indexed: 11/22/2022]
Abstract
The current review aims to outline the likely medical applications of nanotechnology and the potential of the emerging field of nanomedicine. Nanomedicine can be defined as the investigation area encompassing the design of diagnostics and therapeutics at the nanoscale, including nanobots, nanobiosensors, nanoparticles and other nanodevices, for the remediation, prevention and diagnosis of a variety of illnesses. The ultimate goal of nanomedicine is to improve patient quality-of-life. Because nanomedicine includes the rational design of an enormous number of nanotechnology-based products focused on miscellaneous diseases, a variety of nanomaterials can be employed. Therefore, this review will focus on recent advances in the manufacture of soft matterbased nanomedicines specifically designed to improve diagnostics and cancer chemotherapy efficacy. It will be particularly highlighted liposomes, polymer-drug conjugates, drug-loaded block copolymer micelles and biodegradable polymeric nanoparticles, emphasizing the current investigations and potential novel approaches towards overcoming the remaining challenges in the field as well as formulations that are in clinical trials and marketed products.
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Vassilev L, Ranki T, Joensuu T, Jäger E, Karbach J, Wahle C, Partanen K, Kairemo K, Alanko T, Turkki R, Linder N, Lundin J, Ristimäki A, Kankainen M, Hemminki A, Backman C, Dienel K, von Euler M, Haavisto E, Hakonen T, Juhila J, Jäderberg M, Priha P, Vuolanto A, Pesonen S. Repeated intratumoral administration of ONCOS-102 leads to systemic antitumor CD8 + T-cell response and robust cellular and transcriptional immune activation at tumor site in a patient with ovarian cancer. Oncoimmunology 2015; 4:e1017702. [PMID: 26140248 PMCID: PMC4485730 DOI: 10.1080/2162402x.2015.1017702] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 02/05/2015] [Accepted: 02/06/2015] [Indexed: 12/04/2022] Open
Abstract
Adenoviruses are excellent immunotherapeutic agents with a unique ability to prime and boost immune responses. Recombinant adenoviruses cause immunogenic cancer cell death and subsequent release of tumor antigens for antigen presenting cells, resulting in the priming of potent tumor-specific immunity. This effect may be further enhanced by immune-stimulating transgenes expressed by the virus. We report a case of a 38-year-old female with Stage 3 metastatic micropapillary serous carcinoma of the ovary. She was treated in a Phase I study with a granulocyte-macrophage colony stimulating factor (GMCSF)-expressing oncolytic adenovirus, Ad5/3-D24-GMCSF (ONCOS-102). The treatment resulted in progressive infiltration of CD8+ lymphocytes into the tumor and concomitant systemic induction of several tumor-specific CD8+ T-cell populations. The patient was alive at the latest follow up more than 20 months after initiation of the study.
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Petrova S, Venturini CG, Jäger A, Jäger E, Hrubý M, Pavlova E, Štěpánek P. Supramolecular self-assembly of novel thermo-responsive double-hydrophilic and hydrophobic Y-shaped [MPEO-b-PEtOx-b-(PCL)2] terpolymers. RSC Adv 2015. [DOI: 10.1039/c5ra08298f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Nonlinear amphiphilic block copolymer architectures with precisely controlled structures bring new challenges to biomedical materials research.
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Jäger A, Jäger E, Surman F, Höcherl A, Angelov B, Ulbrich K, Drechsler M, Garamus VM, Rodriguez-Emmenegger C, Nallet F, Štěpánek P. Nanoparticles of the poly([N-(2-hydroxypropyl)]methacrylamide)-b-poly[2-(diisopropylamino)ethyl methacrylate] diblock copolymer for pH-triggered release of paclitaxel. Polym Chem 2015. [DOI: 10.1039/c5py00567a] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The potential of self-assembled nanoparticles for in vitro cytostatic activity has been explored on cancer cells.
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Jäger E, Donato RK, Perchacz M, Jäger A, Surman F, Höcherl A, Konefał R, Donato KZ, Venturini CG, Bergamo VZ, Schrekker HS, Fuentefria AM, Raucci MG, Ambrosio L, Štěpánek P. Biocompatible succinic acid-based polyesters for potential biomedical applications: fungal biofilm inhibition and mesenchymal stem cell growth. RSC Adv 2015. [DOI: 10.1039/c5ra15858c] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Poly(alkene succinates) are promising materials for specialized medical devices and tissue engineering, presenting intrinsic properties, such as; fungal biofilm inhibition, biocompatibility and stem cells controlled growth promotion.
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Even J, Yakushev A, Düllmann CE, Haba H, Asai M, Sato TK, Brand H, Di Nitto A, Eichler R, Fan FL, Hartmann W, Huang M, Jäger E, Kaji D, Kanaya J, Kaneya Y, Khuyagbaatar J, Kindler B, Kratz JV, Krier J, Kudou Y, Kurz N, Lommel B, Miyashita S, Morimoto K, Morita K, Murakami M, Nagame Y, Nitsche H, Ooe K, Qin Z, Schädel M, Steiner J, Sumita T, Takeyama M, Tanaka K, Toyoshima A, Tsukada K, Türler A, Usoltsev I, Wakabayashi Y, Wang Y, Wiehl N, Yamaki S. Nuclear chemistry. Synthesis and detection of a seaborgium carbonyl complex. Science 2014; 345:1491-3. [PMID: 25237098 DOI: 10.1126/science.1255720] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Experimental investigations of transactinoide elements provide benchmark results for chemical theory and probe the predictive power of trends in the periodic table. So far, in gas-phase chemical reactions, simple inorganic compounds with the transactinoide in its highest oxidation state have been synthesized. Single-atom production rates, short half-lives, and harsh experimental conditions limited the number of experimentally accessible compounds. We applied a gas-phase carbonylation technique previously tested on short-lived molybdenum (Mo) and tungsten (W) isotopes to the preparation of a carbonyl complex of seaborgium, the 106th element. The volatile seaborgium complex showed the same volatility and reactivity with a silicon dioxide surface as those of the hexacarbonyl complexes of the lighter homologs Mo and W. Comparison of the product's adsorption enthalpy with theoretical predictions and data for the lighter congeners supported a Sg(CO)6 formulation.
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de Castro CE, Mattei B, Riske KA, Jäger E, Jäger A, Stepánek P, Giacomelli FC. Understanding the structural parameters of biocompatible nanoparticles dictating protein fouling. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:9770-9779. [PMID: 25068509 DOI: 10.1021/la502179f] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The development of nanocarriers for biomedical applications requires that these nanocarriers have special properties, including resistance to nonspecific protein adsorption. In this study, the fouling properties of PLA- and PCL-based block copolymer nanoparticles (NPs) have been evaluated by placing them in contact with model proteins. Block copolymer NPs were produced through the self-assembly of PEOm-b-PLAn and PEOm-b-PCLn. This procedure yielded nanosized objects with distinct structural features dependent on the length of the hydrophobic and hydrophilic blocks and the volume ratio. The protein adsorption events were examined in relation to size, chain length, surface curvature, and hydrophilic chain density. Fouling by BSA and lysozyme was considerably reduced as the length of the hydrophilic PEO-stabilizing shell increases. In contrast to the case of hydrophilic polymer-grafted planar surfaces, the current investigations suggest that the hydrophilic chain density did not markedly influence protein fouling. The protein adsorption took place at the outer surface of the NPs since neither BSA nor lysozyme was able to diffuse within the hydrophilic layer due to geometric restrictions. Protein binding is an exothermic process, and it is modulated mainly by polymer features. The secondary structures of BSA and lysozyme were not affected by the adhesion phenomena.
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Khuyagbaatar J, Yakushev A, Düllmann CE, Ackermann D, Andersson LL, Asai M, Block M, Boll RA, Brand H, Cox DM, Dasgupta M, Derkx X, Di Nitto A, Eberhardt K, Even J, Evers M, Fahlander C, Forsberg U, Gates JM, Gharibyan N, Golubev P, Gregorich KE, Hamilton JH, Hartmann W, Herzberg RD, Heßberger FP, Hinde DJ, Hoffmann J, Hollinger R, Hübner A, Jäger E, Kindler B, Kratz JV, Krier J, Kurz N, Laatiaoui M, Lahiri S, Lang R, Lommel B, Maiti M, Miernik K, Minami S, Mistry A, Mokry C, Nitsche H, Omtvedt JP, Pang GK, Papadakis P, Renisch D, Roberto J, Rudolph D, Runke J, Rykaczewski KP, Sarmiento LG, Schädel M, Schausten B, Semchenkov A, Shaughnessy DA, Steinegger P, Steiner J, Tereshatov EE, Thörle-Pospiech P, Tinschert K, Torres De Heidenreich T, Trautmann N, Türler A, Uusitalo J, Ward DE, Wegrzecki M, Wiehl N, Van Cleve SM, Yakusheva V. 48Ca+249Bk fusion reaction leading to element Z = 117: long-lived α-decaying 270Db and discovery of 266Lr. PHYSICAL REVIEW LETTERS 2014; 112:172501. [PMID: 24836239 DOI: 10.1103/physrevlett.112.172501] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Indexed: 06/03/2023]
Abstract
The superheavy element with atomic number Z=117 was produced as an evaporation residue in the (48)Ca+(249)Bk fusion reaction at the gas-filled recoil separator TASCA at GSI Darmstadt, Germany. The radioactive decay of evaporation residues and their α-decay products was studied using a detection setup that allowed measuring decays of single atomic nuclei with half-lives between sub-μs and a few days. Two decay chains comprising seven α decays and a spontaneous fission each were identified and are assigned to the isotope (294)117 and its decay products. A hitherto unknown α-decay branch in (270)Db (Z = 105) was observed, which populated the new isotope (266)Lr (Z = 103). The identification of the long-lived (T(1/2) = 1.0(-0.4)(+1.9) h) α-emitter (270)Db marks an important step towards the observation of even more long-lived nuclei of superheavy elements located on an "island of stability."
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Banzer W, Bernhörster M, Schmidt K, Niederer D, Lungwitz A, Thiel C, Jäger E, Vogt L. Changes in exercise capacity, quality of life and fatigue in cancer patients during an intervention. Eur J Cancer Care (Engl) 2014; 23:624-9. [DOI: 10.1111/ecc.12201] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/26/2014] [Indexed: 11/30/2022]
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Forsberg U, Rudolph D, Golubev P, Sarmiento L, Yakushev A, Andersson LL, Nitto AD, Düllmann C, Gates J, Gregorich K, Gross C, Heßberger F, Herzberg RD, Khuyagbaatar J, Kratz J, Rykaczewski K, Schädel M, Åberg S, Ackermann D, Block M, Brand H, Carlsson B, Cox D, Derkx X, Eberhardt K, Even J, Fahlander C, Gerl J, Jäger E, Kindler B, Krier J, Kojouharov I, Kurz N, Lommel B, Mistry A, Mokry C, Nitsche H, Omtvedt J, Papadakis P, Ragnarsson I, Runke J, Schaffner H, Schausten B, Thörle-Pospiech P, Torres T, Traut T, Trautmann N, Türler A, Ward A, Ward D, Wiehl AN. Spectroscopic Tools Applied to Element Z = 115 Decay Chains. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20146602036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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48
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Petrova S, Jäger E, Konefał R, Jäger A, Venturini CG, Spěváček J, Pavlova E, Štěpánek P. Novel poly(ethylene oxide monomethyl ether)-b-poly(ε-caprolactone) diblock copolymers containing a pH-acid labile ketal group as a block linkage. Polym Chem 2014. [DOI: 10.1039/c4py00114a] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Acidic physiological conditions trigger degradation of amphiphilic block copolymers containing a ketal group as a block linkage into biocompatible degradation products.
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Friedmann I, Atmaca A, Chow KU, Jäger E, Weidmann E. Synergistic Effects of Valproic Acid and Mitomycin C in Adenocarcinoma Cell Lines and Fresh Tumor Cells of Patients with Colon Cancer. J Chemother 2013; 18:415-20. [PMID: 17024798 DOI: 10.1179/joc.2006.18.4.415] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Valproic acid has been demonstrated to mediate cytotoxic effects against tumor cells by acting as a histone-deacetylase inhibitor. However, to date, there are only limited data on the effects of valproic acid in colon cancer. Moreover, information regarding combinations of the drug with chemotherapeutic agents is very limited. The latter is of interest as there is increasing evidence for synergism between so-called "molecular targeting drugs" and chemotherapy. We first demonstrated that valproic acid dose-dependently reduced the viability of adenocarcimona cell lines. After co-incubation with a variety of chemotherapeutic agents, only valproic acid in combination with mitomycin C consistently induced synergistic growth inhibition in all cell lines. To confirm these results in an ex vivo situation, five samples of fresh colon cancer cells were studied. Again, the effect of valproic acid on the viability of the fresh tumor cells was dose dependent. In four of five samples of freshly isolated colon cancer cells, the synergistic effect of valproic acid and mitomycin C on the inhibition of cell growth was confirmed by calculation of the combination index by multiple drug effect analysis. In conclusion, this is the first demonstration that valproic acid as a model substance for histone-deacetylase inhibitors is effective in tumor cells freshly isolated from patients with colon cancer and that the combination of mitomycin C and valproic acid synergistically decreases viability of colon cancer cells.
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Rudolph D, Forsberg U, Golubev P, Sarmiento LG, Yakushev A, Andersson LL, Di Nitto A, Düllmann CE, Gates JM, Gregorich KE, Gross CJ, Heßberger FP, Herzberg RD, Khuyagbaatar J, Kratz JV, Rykaczewski K, Schädel M, Åberg S, Ackermann D, Block M, Brand H, Carlsson BG, Cox D, Derkx X, Eberhardt K, Even J, Fahlander C, Gerl J, Jäger E, Kindler B, Krier J, Kojouharov I, Kurz N, Lommel B, Mistry A, Mokry C, Nitsche H, Omtvedt JP, Papadakis P, Ragnarsson I, Runke J, Schaffner H, Schausten B, Thörle-Pospiech P, Torres T, Traut T, Trautmann N, Türler A, Ward A, Ward DE, Wiehl N. Spectroscopy of element 115 decay chains. PHYSICAL REVIEW LETTERS 2013; 111:112502. [PMID: 24074079 DOI: 10.1103/physrevlett.111.112502] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Indexed: 06/02/2023]
Abstract
A high-resolution α, x-ray, and γ-ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum für Schwerionenforschung. Thirty correlated α-decay chains were detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chains to originate from element Z=115. For the first time, precise spectroscopy allows the derivation of excitation schemes of isotopes along the decay chains starting with elements Z>112. Comprehensive Monte Carlo simulations accompany the data analysis. Nuclear structure models provide a first level interpretation.
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