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van der Zwaan I, Franek F, Fransson R, Tehler U, Frenning G. Characterization of Membrane-Type Dissolution Profiles of Clinically Available Orally Inhaled Products Using a Weibull Fit and a Mechanistic Model. Mol Pharm 2022; 19:3114-3124. [PMID: 35939615 PMCID: PMC9449970 DOI: 10.1021/acs.molpharmaceut.2c00177] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Dissolution rate impacts the absorption rate of poorly soluble inhaled drugs. In vitro dissolution tests that can capture the impact of changes in critical quality attributes of the drug product on in vivo dissolution are important for the development of products containing poorly soluble drugs, as well as modified release formulations. In this study, an extended mathematical model allowing for dissolution of polydisperse powders and subsequent diffusion of dissolved drug across a membrane is described. In vitro dissolution profiles of budesonide, fluticasone propionate, and beclomethasone dipropionate delivered from three commercial drug products were determined using a membrane-type Transwell dissolution test, which consists of a donor and an acceptor compartment separated by a membrane. Subsequently, the profiles were analyzed using the developed mechanistic model and a semi-empirical model based on the Weibull distribution. The two mathematical models provided the same rank order of the performance of the three drug products in terms of dissolution rates, but the rates were significantly different. The faster rate extracted from the mechanistic model is expected to reflect the true dissolution rate of the drug; the Weibull model provides an effective and slower rate that represents not only drug dissolution but also diffusion across the Transwell membrane. In conclusion, the developed extended model provides superior understanding of the dissolution mechanisms in membrane-type (Transwell) dissolution tests.
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Affiliation(s)
- Irès van der Zwaan
- Department of Pharmaceutical Biosciences and the Swedish Drug Delivery Center (SweDeliver), Uppsala University, P.O. Box 580, 751 23 Uppsala, Sweden
| | - Frans Franek
- Advanced Drug Delivery, Pharmaceutical Sciences, R&D, AstraZeneca, 43183 Gothenburg, Sweden
| | - Rebecca Fransson
- Advanced Drug Delivery, Pharmaceutical Sciences, R&D, AstraZeneca, 43183 Gothenburg, Sweden
| | - Ulrika Tehler
- Advanced Drug Delivery, Pharmaceutical Sciences, R&D, AstraZeneca, 43183 Gothenburg, Sweden
| | - Göran Frenning
- Department of Pharmaceutical Biosciences and the Swedish Drug Delivery Center (SweDeliver), Uppsala University, P.O. Box 580, 751 23 Uppsala, Sweden
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2
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La Zara D, Sun F, Zhang F, Franek F, Balogh Sivars K, Horndahl J, Bates S, Brännström M, Ewing P, Quayle MJ, Petersson G, Folestad S, van Ommen JR. Controlled Pulmonary Delivery of Carrier-Free Budesonide Dry Powder by Atomic Layer Deposition. ACS Nano 2021; 15:6684-6698. [PMID: 33769805 PMCID: PMC8155342 DOI: 10.1021/acsnano.0c10040] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 03/22/2021] [Indexed: 06/12/2023]
Abstract
Ideal controlled pulmonary drug delivery systems provide sustained release by retarding lung clearance mechanisms and efficient lung deposition to maintain therapeutic concentrations over prolonged time. Here, we use atomic layer deposition (ALD) to simultaneously tailor the release and aerosolization properties of inhaled drug particles without the need for lactose carrier. In particular, we deposit uniform nanoscale oxide ceramic films, such as Al2O3, TiO2, and SiO2, on micronized budesonide particles, a common active pharmaceutical ingredient for the treatment of respiratory diseases. In vitro dissolution and ex vivo isolated perfused rat lung tests demonstrate dramatically slowed release with increasing nanofilm thickness, regardless of the nature of the material. Ex situ transmission electron microscopy at various stages during dissolution unravels mostly intact nanofilms, suggesting that the release mechanism mainly involves the transport of dissolution media through the ALD films. Furthermore, in vitro aerosolization testing by fast screening impactor shows a ∼2-fold increase in fine particle fraction (FPF) for each ALD-coated budesonide formulation after 10 ALD process cycles, also applying very low patient inspiratory pressures. The higher FPFs after the ALD process are attributed to the reduction in the interparticle force arising from the ceramic surfaces, as evidenced by atomic force microscopy measurements. Finally, cell viability, cytokine release, and tissue morphology analyses verify a safe and efficacious use of ALD-coated budesonide particles at the cellular level. Therefore, surface nanoengineering by ALD is highly promising in providing the next generation of inhaled formulations with tailored characteristics of drug release and lung deposition, thereby enhancing controlled pulmonary delivery opportunities.
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Affiliation(s)
- Damiano La Zara
- Department
of Chemical Engineering, Delft University
of Technology, Van der Maasweg 9, Delft, 2629HZ, The Netherlands
| | - Feilong Sun
- Department
of Chemical Engineering, Delft University
of Technology, Van der Maasweg 9, Delft, 2629HZ, The Netherlands
| | - Fuweng Zhang
- Department
of Chemical Engineering, Delft University
of Technology, Van der Maasweg 9, Delft, 2629HZ, The Netherlands
| | - Frans Franek
- Advanced
Drug Delivery, Pharmaceutical Sciences, R&D, AstraZeneca, Gothenburg, Sweden
| | - Kinga Balogh Sivars
- Clinical
Testing and Precision Medicine, Global Procurement, Operations, AstraZeneca, Gothenburg, Sweden
| | - Jenny Horndahl
- Bioscience
COPD/IPF, Research and Early Development, Respiratory & Immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Stephanie Bates
- Functional
and Mechanistic Safety, Clinical Pharmacology
and Safety Sciences, R&D, AstraZeneca, Cambridge U.K.
| | - Marie Brännström
- Drug
Metabolism and Pharmacokinetics, Research and Early Development, Respiratory & Immunology, BioPharmaceuticals R&D,
AstraZeneca, Gothenburg, Sweden
| | - Pär Ewing
- Drug
Metabolism and Pharmacokinetics, Research and Early Development, Respiratory & Immunology, BioPharmaceuticals R&D,
AstraZeneca, Gothenburg, Sweden
| | - Michael J. Quayle
- New Modalities
and Parenteral Development, Pharmaceutical Technology & Development, Operations, AstraZeneca, Gothenburg, Sweden
| | - Gunilla Petersson
- Innovation
Strategy and External Liaison, Pharmaceutical Technology & Development, Operations, AstraZeneca, Gothenburg, Sweden
| | - Staffan Folestad
- Innovation
Strategy and External Liaison, Pharmaceutical Technology & Development, Operations, AstraZeneca, Gothenburg, Sweden
| | - J. Ruud van Ommen
- Department
of Chemical Engineering, Delft University
of Technology, Van der Maasweg 9, Delft, 2629HZ, The Netherlands
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3
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Ahmad A, Pepin X, Aarons L, Wang Y, Darwich AS, Wood JM, Tannergren C, Karlsson E, Patterson C, Thörn H, Ruston L, Mattinson A, Carlert S, Berg S, Murphy D, Engman H, Laru J, Barker R, Flanagan T, Abrahamsson B, Budhdeo S, Franek F, Moir A, Hanisch G, Pathak SM, Turner D, Jamei M, Brown J, Good D, Vaidhyanathan S, Jackson C, Nicolas O, Beilles S, Nguefack JF, Louit G, Henrion L, Ollier C, Boulu L, Xu C, Heimbach T, Ren X, Lin W, Nguyen-Trung AT, Zhang J, He H, Wu F, Bolger MB, Mullin JM, van Osdol B, Szeto K, Korjamo T, Pappinen S, Tuunainen J, Zhu W, Xia B, Daublain P, Wong S, Varma MV, Modi S, Schäfer KJ, Schmid K, Lloyd R, Patel A, Tistaert C, Bevernage J, Nguyen MA, Lindley D, Carr R, Rostami-Hodjegan A. IMI – Oral biopharmaceutics tools project – Evaluation of bottom-up PBPK prediction success part 4: Prediction accuracy and software comparisons with improved data and modelling strategies. Eur J Pharm Biopharm 2020; 156:50-63. [DOI: 10.1016/j.ejpb.2020.08.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 06/12/2020] [Accepted: 08/06/2020] [Indexed: 11/25/2022]
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Abstract
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Impactor-type
dose deposition is a common prerequisite for dissolution
testing of inhaled medicines, and drug release typically takes place
through a membrane. The purpose of this work is to develop a mechanistic
model for such combined dissolution and release processes, focusing
on a drug that initially is present in solid form. Our starting points
are the Noyes–Whitney (or Nernst–Brunner) equation and
Fick’s law. A detailed mechanistic analysis of the drug release
process is provided, and approximate closed-form expressions for the
amount of the drug that remains in solid form and the amount of the
drug that has been released are derived. Comparisons with numerical
data demonstrated the accuracy of the approximate expressions. Comparisons
with experimental release data from literature demonstrated that the
model can be used to establish rate-controlling release mechanisms.
In conclusion, the model constitutes a valuable tool for the analysis
of in vitro dissolution data for inhaled drugs.
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Affiliation(s)
- Göran Frenning
- Department of Pharmacy and the Swedish Drug Delivery Center (SweDeliver), Uppsala University, P.O. Box 580, 751 23 Uppsala, Sweden
| | - Irès van der Zwaan
- Department of Pharmacy and the Swedish Drug Delivery Center (SweDeliver), Uppsala University, P.O. Box 580, 751 23 Uppsala, Sweden
| | - Frans Franek
- Inhaled Product Development, Pharmaceutical Technology & Development, AstraZeneca, 43183 Gothenburg, Sweden
| | - Rebecca Fransson
- Advanced Drug Delivery, Pharmaceutical Sciences, R&D, AstraZeneca, 43183 Gothenburg, Sweden
| | - Ulrika Tehler
- Advanced Drug Delivery, Pharmaceutical Sciences, R&D, AstraZeneca, 43183 Gothenburg, Sweden
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Stojanović B, Bauer C, Stotter C, Klestil T, Nehrer S, Franek F, Rodríguez Ripoll M. Tribocorrosion of a CoCrMo alloy sliding against articular cartilage and the impact of metal ion release on chondrocytes. Acta Biomater 2019; 94:597-609. [PMID: 31226479 DOI: 10.1016/j.actbio.2019.06.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 06/11/2019] [Accepted: 06/13/2019] [Indexed: 01/22/2023]
Abstract
Partial knee replacement and hemiarthroplasty are some of the orthopedic procedures resulting in a metal on cartilage interface. As metal implant material, CoCrMo based alloys are commonly used. The aim of the present study is to assess the role of biotribocorrosion on the CoCrMo-cartilage interface with an emphasis on metal release during sliding contact. The biotribocorrosion experiments were performed under controlled electrochemical conditions using a floating cell with a three electrode set up coupled to a microtribometer. Throughout the experiment the coefficient of friction and the open circuit potential were monitored. Analyses of the electrolyte after the experiment show that metal release can occur during sliding contact of CoCrMo alloy against articular cartilage despite the extraordinary low coefficient of friction measured. Metal release is attributed to changes in passive layer caused at the onset of sliding. The released metal was found to be forming compounds with potential cytotoxicity. Since the presence of metal ions in the cartilage matrix can potentially lead to cell apoptosis, the metabolic activity of human osteoarthritic chondrocytes (2D-cultures) was investigated in the presence of phosphate buffered saline containing metal ions using XTT-assay. The experiments indicate that critical concentrations of Co ions lead to a significant decrease in chondrocyte metabolic activity. Therefore, biotribocorrosion is a mechanism that can occur in partial replacements and lead to chondrocyte apoptosis thus playing a role in the observed accelerated degradation of the remaining cartilage tissue after the mentioned orthopedic procedures. STATEMENT OF SIGNIFICANCE: Partial replacements provide an alternative to total joint replacements. This procedure is less invasive, allows a faster rehabilitation and provides a better function of the joint. However, the remaining native cartilage experiences accelerated degradation when in contact with metallic implant components. This work investigates the role of tribocorrosion at the metal-cartilage interface during sliding. Tribocorrosion is a degradation process that can alter significantly the wear rates experienced by metallic implants and lead to the release of metal ions and particles. The released metal can form compounds with potential cytotoxicity on cartilage tissue. The knowledge gained in this work will serve to understand the mechanisms behind the failure of partial replacements and develop future biomaterials with an enhanced lifetime.
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Affiliation(s)
- B Stojanović
- AC2T research GmbH, Viktor Kaplan-Straße 2/C, A-2700 Wiener Neustadt, Austria
| | - C Bauer
- Danube University Krems, Faculty of Health and Medicine, Department for Health Sciences and Biomedicine, Center for Regenerative Medicine and Orthopedics, Dr. Karl-Dorrek-Str. 30, A-3500 Krems, Austria
| | - C Stotter
- Danube University Krems, Faculty of Health and Medicine, Department for Health Sciences and Biomedicine, Center for Regenerative Medicine and Orthopedics, Dr. Karl-Dorrek-Str. 30, A-3500 Krems, Austria; LK Baden-Mödling-Hainburg, Department of Orthopedics and Traumatology, Waltersdorferstraße 75, A-2500 Baden, Austria
| | - T Klestil
- LK Baden-Mödling-Hainburg, Department of Orthopedics and Traumatology, Waltersdorferstraße 75, A-2500 Baden, Austria; Danube University Krems, Faculty of Health and Medicine, Department for Health Sciences and Biomedicine, Center for Medical Specializations, Dr. Karl-Dorrek-Str. 30, A-3500 Krems, Austria
| | - S Nehrer
- Danube University Krems, Faculty of Health and Medicine, Department for Health Sciences and Biomedicine, Center for Regenerative Medicine and Orthopedics, Dr. Karl-Dorrek-Str. 30, A-3500 Krems, Austria
| | - F Franek
- AC2T research GmbH, Viktor Kaplan-Straße 2/C, A-2700 Wiener Neustadt, Austria
| | - M Rodríguez Ripoll
- AC2T research GmbH, Viktor Kaplan-Straße 2/C, A-2700 Wiener Neustadt, Austria.
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6
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Franek F, Fransson R, Thörn H, Bäckman P, Andersson PU, Tehler U. Ranking in Vitro Dissolution of Inhaled Micronized Drug Powders including a Candidate Drug with Two Different Particle Sizes. Mol Pharm 2018; 15:5319-5326. [DOI: 10.1021/acs.molpharmaceut.8b00796] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Frans Franek
- Pharmaceutical Technology & Development Inhalation, Operations, AstraZeneca R&D, Pepparedsleden 1, Mölndal 43183, Sweden
| | - Rebecca Fransson
- Pharmaceutical Sciences, IMED, AstraZeneca R&D, Pepparedsleden 1, Mölndal 43183, Sweden
| | - Helena Thörn
- Pharmaceutical Technology & Development Inhalation, Operations, AstraZeneca R&D, Pepparedsleden 1, Mölndal 43183, Sweden
| | - Per Bäckman
- Pharmaceutical Technology & Development Inhalation, Operations, AstraZeneca R&D, Pepparedsleden 1, Mölndal 43183, Sweden
| | - Patrik U. Andersson
- Pharmaceutical Technology & Development Inhalation, Operations, AstraZeneca R&D, Pepparedsleden 1, Mölndal 43183, Sweden
| | - Ulrika Tehler
- Pharmaceutical Sciences, IMED, AstraZeneca R&D, Pepparedsleden 1, Mölndal 43183, Sweden
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7
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Franek F, Jarlfors A, Larsen F, Holm P, Steffansen B. In vitro solubility, dissolution and permeability studies combined with semi-mechanistic modeling to investigate the intestinal absorption of desvenlafaxine from an immediate- and extended release formulation. Eur J Pharm Sci 2015; 77:303-13. [DOI: 10.1016/j.ejps.2015.06.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 05/31/2015] [Accepted: 06/15/2015] [Indexed: 12/11/2022]
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8
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Franek F, Holm P, Larsen F, Steffansen B. Interaction between fed gastric media (Ensure Plus®) and different hypromellose based caffeine controlled release tablets: comparison and mechanistic study of caffeine release in fed and fasted media versus water using the USP dissolution apparatus 3. Int J Pharm 2013; 461:419-26. [PMID: 24342711 DOI: 10.1016/j.ijpharm.2013.12.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 12/04/2013] [Accepted: 12/06/2013] [Indexed: 11/29/2022]
Abstract
The aim of the study was to investigate caffeine release in fed and fasted state media from three controlled release matrix tablets containing different HPMC viscosity grades. The biorelevant in vitro dissolution methods utilize the USP 3 dissolution apparatus and biorelevant media to simulate fed and fasted gastro-intestinal dissolution conditions. The effect of tablet reciprocation rate (dip speed) in dissolution media (10 and 15 dips per minute) and media (water, fed and fasted) on caffeine release rate from - and erosion rate of - 100, 4000 and 15,000 mPa s HPMC viscosity tablets was investigated using factorial designed experiments. Furthermore, the mechanism of release in Ensure Plus(®), a nutrition drink similar in composition to the FDA standard meal, was investigated by studying tablet swelling using texture analysis. Altering dip speed has negligible effect on release and erosion rates. Using fasted media instead of water slightly decreases caffeine release from 100 and 4000 mPa s HPMC viscosity tablets as well as erosion rates, while 15,000 mPa s tablets remain unaffected. Fed compared to fasted media decreases caffeine release rate, and the food effect is greater for the 100 mPa s viscosity tablets compared to the 4000 and 15,000 mPa s viscosity tablets. The investigation using texture analysis indicates that Ensure Plus(®) becomes rate-limiting for caffeine release from HPMC tablets by forming a hydrophobic barrier around the tablets. The barrier decreases tablet water permeation, which decreases erosion rate in 100 mPa s viscosity tablets, swelling in 15,000 mPa s viscosity tablets and caffeine release from both tablets. This observed interaction between Ensure Plus(®) and the HPMC tablets may translate into decreased drug release rate in the fed stomach, which may decrease the amount of drug available for absorption in the small intestine and thus reduce systemic drug exposure and maximum plasma concentration.
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Affiliation(s)
- Frans Franek
- Section for Pharmaceutical Design and Drug Delivery, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 København Ø, Denmark
| | - Per Holm
- Biologics and Pharmaceutical Science, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark
| | - Frank Larsen
- Clinical Pharmacology, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark
| | - Bente Steffansen
- Section for Pharmaceutical Design and Drug Delivery, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 København Ø, Denmark.
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9
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Franek F, Holý A, Votruba I, Eckschlager T. Modulation of cell cycle progression and of antibody production in mouse hybridomas by a nucleotide analogue. Cytotechnology 2011; 28:65-72. [PMID: 19003408 DOI: 10.1023/a:1008017328061] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The nucleotide analogue 9-[2-(phosphonomethoxy)ethyl]guanine (PMEG) has been identified as a powerful antiproliferative substance when acting on hybridoma cells. In the range of 10 nM to 100 nM concentrations this agent reduces cell growth rate, while its apoptosis-inducing activity is marginal. Marked induction of apoptosis can be observed at micromolar and higher order concentrations. In PMEG-supplemented media the cell cycle progression is perturbed, the flow-cytometric DNA profile shows a higher proportion of cells in the S and G2/M phases of the cell cycle. Concomitantly with the reduction of the growth rate, the specific monoclonal antibody production rate may rise by 20-27%. Addition of PMEG at the end of the exponential phase of a batch culture results in an enhancement of the final monoclonal antibody concentration.
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Affiliation(s)
- F Franek
- Academy of Sciences, Institute of Molecular Genetics, Videnska 1083, CZ-14220, Praha 4, Czech Republic,
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10
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Franek F, Strnad M, Havlícek L, Siglerová V, Fismolová I, Eckschlager T. Diverse effects of the cyclin-dependent kinase inhibitor bohemine: Concentration- and time-dependent suppression or stimulation of hybridoma culture. Cytotechnology 2011; 36:117-23. [PMID: 19003322 DOI: 10.1023/a:1014020415912] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
An analog of aromatic cytokinins, the 2,6,9-trisubstituted purine derivative bohemine, was applied to cultures of mouse hybridoma cells in order to analyze its capacity of suppressing cell growth and maintaining or enhancing the production of monoclonal antibody. Addition of bohemine at concentrations in the range of1-10 muM resulted in a short-term arrest of growth and of monoclonal antibody production. The short-term suppression of cell functions was followed by a significant temporary increase of specific growth rate and of specific production rate. The steady-state viable cell density values, found in semicontinuous cultures, showed a certain stimulation of cell growth in the range of micromolar concentrations of bohemine, and inhibition of growth at 10 and 30 muM concentrations. The profiles of cell cycle phases indicated that hybridoma cells are retarded both at the G(1)/S boundary and at the G(2)/M boundary, depending on bohemine concentration. The existence of the sequence of events,from suppression to stimulation, suggests that bohemine probably modulates more than one regulatory pathway in the cell.
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Affiliation(s)
- F Franek
- Laboratory of Growth Regulators, Institute of Experimental Botany, Academy of Sciences of the Czech Republic, 10227, Praha 10, Czech Republic,
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11
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Tomastik C, Jech M, Wopelka T, Franek F. Surface analysis of cylinder liners from tribological model experiments and internal combustion engines. SURF INTERFACE ANAL 2010. [DOI: 10.1002/sia.3329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Franek F, Rosa A. Corrigendum to: “ Two-factorizations of small complete graphs”. J Stat Plan Inference 2008. [DOI: 10.1016/j.jspi.2008.05.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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13
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Franek F, Hohenwarter O, Katinger H. Plant protein hydrolysates: preparation of defined peptide fractions promoting growth and production in animal cells cultures. Biotechnol Prog 2000; 16:688-92. [PMID: 11027157 DOI: 10.1021/bp0001011] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new approach was applied with the aim at producing plant protein hydrolysates less heterogeneous and less contaminated with nonpeptide substances than are the presently available digests. A significant reduction of nonprotein contaminants was achieved by extraction of the plant material, soy flour or wheat flour, with acetone prior to isolation of the protein. Enzymes of nonanimal origin, papain or Pronase, were used for protein hydrolysis. The components of the hydrolysates were resolved by low-pressure liquid chromatography. Separation of peptide fractions and of remaining nonpeptide contaminants was achieved using small-pore size-exclusion chromatography matrices, Sephadex G-15 or Biogel P-2. Individual peptide fractions, both from soy protein and from wheat gluten, varied substantially in their growth-promoting and production-enhancing activities when tested on a mouse hybridoma culture in protein-free medium. The highest enhancement of viable cell density in batch cultures was 180% of control, and the highest enhancement of final immunoglobulin concentration was more than 230% of control. The existence of marked differences in activity of individual peptide fractions leads to a suggestion that the hydrolysates may provide peptides exerting specific positive effects on cultured animal cells.
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Affiliation(s)
- F Franek
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Radiova 1, CZ-10227 Prague 10, Czech Republic.
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15
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Franek F, Holy A, Votruba I, Eckschlager T. Acyclic nucleotide analogues suppress growth and induce apoptosis in human leukemia cell lines. Int J Oncol 1999; 14:745-52. [PMID: 10087324 DOI: 10.3892/ijo.14.4.745] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Acyclic nucleotide analogues perturb DNA replication by terminating the growing DNA chain. The analogues selected for testing on human leukemia cell lines, namely 9-[2-(phosphonomethoxy)ethyl]adenine (PMEA), 9-[2-(phosphonomethoxy)ethyl]-2,6-diaminopurine (PMEDAP), and 9-[2-(phosphonomethoxy)ethyl]guanine (PMEG) exhibited growth-inhibiting activity at low concentrations, and apoptosis-inducing activity at high concentrations. A common feature was a reduction of the proportion of G1 cell cycle phase. Activities of the analogues increased in the order PMEA<PMEDAP<PMEG. The lymphoid cell line MOLT-4 was more susceptible to the agents than the myelogenous cell lines HL-60 and ML-1. In semicontinuous cultures in the presence of low-concentration PMEG the steady-state viable cell concentration was lower and the proportion of G1 phase cells was suppressed. Upon gradual removal of PMEG from the medium, the cell concentration and the DNA profile returned to values characteristic for the control culture. It is concluded that low concentrations of the analogues cause reversible slowdown of growth, due to continuous repairing of damaged DNA, while high-concentrations induce apoptosis in irreparably damaged cells.
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Affiliation(s)
- F Franek
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, CZ-14220 Praha 4, Czech Republic
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16
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Stepchenko AG, Luchina NN, Franek F, Polianovskiĭ OL. [Factors interacting with promoter region of immunoglobulin genes. Determination of the binding site boundaries]. Mol Gen Mikrobiol Virusol 1988:20-3. [PMID: 3231228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The nuclear extracts of plasmacytomas producing antibodies were found to contain factors which formed complexes with the promoter fragment of the gene for immunoglobulin kappa-chains. The corresponding complexes found in the extracts of nonlymphoid cells had a different mobility. Two approaches were proposed for determining the boundaries of the region necessary for protein factors to be bound to DNA using nuclease Ba131. A 5'-ATTTGCAT-3' octanucleotide sequence was shown to be necessary for interaction with the protein nuclear factor in the studied plasmacytoma lines. The protein completely lost its affinity if at least one nucleotide was removed or substituted at the 5'- or 3'-end of this sequence. The procedures proposed for determining the precise boundaries of the sequence necessary for protein binding to DNA do not require a preliminary protein purification. The principles on which the procedures are based, set no limitations to their application to other systems used for studying the interaction of proteins with DNA.
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Abstract
The recognition and distinction of pig IgG subclasses is a difficult task because no pathological monoclonal immunoglobulins of pig origin are available. Attempts at elucidating the subclass composition of pig IgG based on subfractionation of pooled IgG and preparation of antisera has led to only partial success. Chemical evidence for heterogeneity of the constant portion of pig gamma-chains pointed to the existence of more than one subclass; a final answer to the question of the number of subclasses could not be obtained. Functionally different antibodies of the IgG class may be isolated from immune sera collected at various stages of the immune response. Precipitating and nonprecipitating anti-dinitro-phenyl (DNP) antibodies differ chiefly in their capacity for forming insoluble complexes with DNP-carrier proteins. Examination of these antibodies by physical methods showed that the precipitating antibody is less compact, more flexible and that the distance between the two binding sites on the same molecule are greater than for the nonprecipitating anti-DNP antibody. The precipitating antibody is very resistant to cleavage by pepsin compared to the non-precipitating antibody. This resistance, together with the differences in the molecular parameters described above provides evidence that precipitating and nonprecipitating anti-DNP antibodies in swine are representatives of separate IgG subclasses. Mouse monoclonal antibodies to pig IgG show a degree of selectivity for certain IgG subpopulations when tested against pooled pig IgG. The limited number of monoclonal antibodies currently available does not allow final conclusions to be drawn on the number of pig IgG subclasses.
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Affiliation(s)
- F Franek
- Department of Membrane Biochemistry, Institute of Molecular Genetics, Videnska, Czechoslovakia
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Abstract
The tension-patterns of the tibiofibular syndesmosis during stance and push-off phases of gait are still unknown. Therefore a strain-gauge study was done, using an anatomically prepared human leg with the syndesmosis removed and the gauges fixed on the bone, avoiding bending influences. Syndesmotic tension forces measured under sequential axial loading up to 500 N in neutral ankle position were 6.5 N for anterior and 10 N for posterior ligaments under maximum load. With 10 degrees ankle dorsiflexion and no load applied about 5 N of tension were measured in each of the anterior and posterior ligaments. Application of axial load under same conditions resulted in a decrease to negligible tension in the anterior ligament and an increase of tension in the posterior ligament. In evaluating the load tests, which were done in 10 degrees dorsiflexion and the so-called neutral-zero-position of the ankle, we found that our data correlated well with the elasticity and tearing resistance, measured by Sauer. According to the pathomechanics of trauma exact measurements of these forces in the weightbearing ankle are of interest for postoperative treatment of ankle fractures.
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Affiliation(s)
- O Wruhs
- I. Universitätsklinik für Unfallchirurgie, Wien
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Affiliation(s)
- J -J. Metzger
- Department of Protein Chemistry, Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Science, Prague, Czechoslovakia
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21
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Franek F. Affinity labeled pig anti-DNP antibody. Position of labeled tyrosine in the lambda chain. Mol Immunol 1970. [DOI: 10.1016/0161-5890(70)90077-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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22
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Affiliation(s)
- J Novotný
- Department of Protein Chemistry, Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, Prague, Czechoslovakia
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Affiliation(s)
- F Franek
- Department of Protein Chemistry, Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, Prague, Czechoslovakia
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de Haas GH, Franek F, Keil B, Thomas DW, Lederer E. Application of mass spectrometry to the analysis of proteins containing a N-terminal pyroglutamic acid residue. FEBS Lett 1969; 4:25-27. [PMID: 11947136 DOI: 10.1016/0014-5793(69)80186-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- G H. de Haas
- Biochemisch Laboratorium der Rijksuniversiteit, Utrecht, Holland
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25
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Franek F, Keil B, Thomas DW, Lederer E. Chemical and mass spectrometric sequence studies of a peptide from the variable part of normal immunoglobulin lambda-chains. FEBS Lett 1969; 2:309-312. [PMID: 11946341 DOI: 10.1016/0014-5793(69)80050-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- F Franek
- Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, Prague, Czechoslovakia
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26
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Affiliation(s)
- J Novotý
- Department of Protein Chemistry, Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, Prague, Czechoslovakia
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27
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Franek F. Synthesis of immunoglobulins. G Mal Infett Parassit 1966; 18:Suppl:962-5. [PMID: 4173178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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