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Bugajska M, Sypien A, Bobrowski P, Korneva A, Morgiel J, Szulc Z, Wojewoda-Budka J. Microstructural Characterization of Nb/Inconel 601 Interface Obtained in the Explosive Welding Process. Microsc Microanal 2021; 28:1-8. [PMID: 34315557 DOI: 10.1017/s1431927621012174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
This work presents the microstructure of the cross-section of a newly developed Nb/Inconel 601 weld with particular attention paid to the continuity, morphology of the interface, and the microstructural changes within its vicinity. Both scanning (SEM) and transmission (TEM) electron microscopy techniques are excellent tools to analyze the microstructure that affects both mechanical and corrosion resistance properties of the obtained product. Grain size examination and their orientation together with the character of grain boundaries by the electron backscattered diffraction (EBSD) technique were performed followed by chemical composition determination across the interface with energy-dispersive X-ray spectroscopy (EDS) in SEM. Then, the microstructure observations of the mixed region located at the Nb/Inconel 601 interface using the TEM technique allowed its chemical and phase composition to be revealed.
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Affiliation(s)
- Monika Bugajska
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Krakow, Poland
| | - Anna Sypien
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Krakow, Poland
| | - Piotr Bobrowski
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Krakow, Poland
| | - Anna Korneva
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Krakow, Poland
| | - Jerzy Morgiel
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Krakow, Poland
| | - Zygmunt Szulc
- High Energy Technologies Works "Explomet", 100H Oswiecimska St., 45-641Opole, Poland
| | - Joanna Wojewoda-Budka
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Krakow, Poland
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Kwiecien I, Wierzbicka-Miernik A, Szczerba M, Bobrowski P, Szulc Z, Wojewoda-Budka J. On the Disintegration of A1050/Ni201 Explosively Welded Clads Induced by Long-Term Annealing. Materials (Basel) 2021; 14:ma14112931. [PMID: 34072349 PMCID: PMC8198445 DOI: 10.3390/ma14112931] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 05/22/2021] [Accepted: 05/25/2021] [Indexed: 11/16/2022]
Abstract
The paper presents the microstructure and phase composition of the interface zone formed in the explosive welding process between technically pure aluminum and nickel. Low and high detonation velocities of 2000 and 2800 m/s were applied to expose the differences of the welded zone directly after the joining as well as subsequent long-term annealing. The large amount of the melted areas was observed composed of a variety of Al-Ni type intermetallics; however, the morphology varied from nearly flat to wavy with increasing detonation velocity. The applied heat treatment at 500 °C has resulted in the formation of Al3Ni and Al3Ni2 layers, which in the first stages of growth preserved the initial interface morphology. Due to the large differences in Al and Ni diffusivities, the porosity formation occurred for both types of clads. Faster consumption of Al3Ni phase at the expense of the growing Al3Ni2 phase, characterized by strong crystallographic texture, has been observed only for the weld obtained at low detonation velocity. As a result of the extended annealing time, the disintegration of the bond occurred due to crack propagation located at the A1050/Al3Ni2 interface.
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Affiliation(s)
- Izabella Kwiecien
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Cracow, Poland; (A.W.-M.); (M.S.); (P.B.); (J.W.-B.)
- Correspondence: ; Tel.: +48-12-295-28-07
| | - Anna Wierzbicka-Miernik
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Cracow, Poland; (A.W.-M.); (M.S.); (P.B.); (J.W.-B.)
| | - Maciej Szczerba
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Cracow, Poland; (A.W.-M.); (M.S.); (P.B.); (J.W.-B.)
| | - Piotr Bobrowski
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Cracow, Poland; (A.W.-M.); (M.S.); (P.B.); (J.W.-B.)
| | - Zygmunt Szulc
- High Energy Technologies Works ‘Explomet’, 100H Oswiecimska St., 45-641 Opole, Poland;
| | - Joanna Wojewoda-Budka
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Cracow, Poland; (A.W.-M.); (M.S.); (P.B.); (J.W.-B.)
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Zemła J, Bobrowska J, Kubiak A, Zieliński T, Pabijan J, Pogoda K, Bobrowski P, Lekka M. Indenting soft samples (hydrogels and cells) with cantilevers possessing various shapes of probing tip. Eur Biophys J 2020; 49:485-495. [PMID: 32803311 PMCID: PMC7456413 DOI: 10.1007/s00249-020-01456-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [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: 02/24/2020] [Revised: 05/06/2020] [Accepted: 08/11/2020] [Indexed: 12/20/2022]
Abstract
The identification of cancer-related changes in cells and tissues based on the measurements of elastic properties using atomic force microscopy (AFM) seems to be approaching clinical application. Several limiting aspects have already been discussed; however, still, no data have shown how specific AFM probe geometries are related to the biomechanical evaluation of cancer cells. Here, we analyze and compare the nanomechanical results of mechanically homogenous polyacrylamide gels and heterogeneous bladder cancer cells measured using AFM probes of various tip geometry, including symmetric and non-symmetric pyramids and a sphere. Our observations show large modulus variability aligned with both types of AFM probes used and with the internal structure of the cells. Altogether, these results demonstrate that it is possible to differentiate between compliant and rigid samples of kPa elasticity; however, simultaneously, they highlight the strong need for standardized protocols for AFM-based elasticity measurements if applied in clinical practice including the use of a single type of AFM cantilever.
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Affiliation(s)
- Joanna Zemła
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342, Kraków, Poland.
| | - Justyna Bobrowska
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342, Kraków, Poland
| | - Andrzej Kubiak
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342, Kraków, Poland
| | - Tomasz Zieliński
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342, Kraków, Poland
| | - Joanna Pabijan
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342, Kraków, Poland
| | - Katarzyna Pogoda
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342, Kraków, Poland
| | - Piotr Bobrowski
- Institute of Metallurgy and Materials Science Polish Academy of Sciences, PL-30059, Kraków, Poland
| | - Małgorzata Lekka
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342, Kraków, Poland.
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Kalita D, Rogal Ł, Bobrowski P, Durejko T, Czujko T, Antolak-Dudka A, Cesari E, Dutkiewicz J. Superelastic Behavior of Ti-Nb Alloys Obtained by the Laser Engineered Net Shaping (LENS) Technique. Materials (Basel) 2020; 13:ma13122827. [PMID: 32586058 PMCID: PMC7344434 DOI: 10.3390/ma13122827] [Citation(s) in RCA: 6] [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] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/19/2020] [Accepted: 06/22/2020] [Indexed: 11/16/2022]
Abstract
The effect of Nb content on microstructure, mechanical properties and superelasticity was investigated for a series of Ti-xNb alloys, fabricated by the laser engineered net shaping method, using elemental Ti and Nb powders. The microstructure of as-deposited materials consisted of columnar β-phase grains, elongated in the built direction. However, due to the presence of undissolved Nb particles during the deposition process, an additional heat treatment was necessary. The observed changes in mechanical properties were explained in relation to the phase constituents and deformation mechanisms. Due to the elevated oxygen content in the investigated materials (2 at.%), the specific deformation mechanisms were observed at lower Nb content in comparison to the conventionally fabricated materials. This made it possible to conclude that oxygen increases the stability of the β phase in β–Ti alloys. For the first time, superelasticity was observed in Ti–Nb-based alloys fabricated by the additive manufacturing method. The highest recoverable strain of 3% was observed in Ti–19Nb alloy as a result of high elasticity and reverse martensitic transformation stress-induced during the loading.
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Affiliation(s)
- Damian Kalita
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25, Reymonta St., 30-059 Krakow, Poland; (Ł.R.); (P.B.); (J.D.)
- Correspondence:
| | - Łukasz Rogal
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25, Reymonta St., 30-059 Krakow, Poland; (Ł.R.); (P.B.); (J.D.)
| | - Piotr Bobrowski
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25, Reymonta St., 30-059 Krakow, Poland; (Ł.R.); (P.B.); (J.D.)
| | - Tomasz Durejko
- Institute of Materials Science and Engineering, Faculty of Advanced Technology and Chemistry, Military University of Technology, 2, Gen. Kaliskiego Str., 00-908 Warsaw, Poland; (T.D.); (T.C.); (A.A.-D.)
| | - Tomasz Czujko
- Institute of Materials Science and Engineering, Faculty of Advanced Technology and Chemistry, Military University of Technology, 2, Gen. Kaliskiego Str., 00-908 Warsaw, Poland; (T.D.); (T.C.); (A.A.-D.)
| | - Anna Antolak-Dudka
- Institute of Materials Science and Engineering, Faculty of Advanced Technology and Chemistry, Military University of Technology, 2, Gen. Kaliskiego Str., 00-908 Warsaw, Poland; (T.D.); (T.C.); (A.A.-D.)
| | - Eduard Cesari
- Department of Physics, University of Balearic Islands, E07122 Palma de Mallorca, Spain;
| | - Jan Dutkiewicz
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25, Reymonta St., 30-059 Krakow, Poland; (Ł.R.); (P.B.); (J.D.)
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Bobrowski P. Estimation of systematic errors committed when approximating length of grain boundaries using edges of rectangular or hexagonal grids of EBSD maps. Micron 2019; 130:102812. [PMID: 31874373 DOI: 10.1016/j.micron.2019.102812] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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: 08/14/2019] [Revised: 12/17/2019] [Accepted: 12/17/2019] [Indexed: 11/19/2022]
Abstract
A method for calculating the overestimation error of grain boundary (GB) length committed when approximating a straight segment of a GB using edges of rectangular or hexagonal grid was given. The relative errors range from 0 % to 41.42 % and from 15.47 % to 33.33 %, for the square and hex grids, respectively. The average error values for both kinds of meshes are the same, namely, 27.32 %. Comparison of the mathematical calculations with experimental results obtained from Electron Backscatter Diffraction (EBSD) data, indicated that the values of the average overestimation errors may be utilized as correction coefficients to adjust experimental data towards more accurate numbers.
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Affiliation(s)
- Piotr Bobrowski
- Institute of Metallurgy and Materials Science of Polish Academy of Sciences, 25 Reymonta Str., PL-30-059, Krakow, Poland.
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Bobrowska J, Awsiuk K, Pabijan J, Bobrowski P, Lekki J, Sowa KM, Rysz J, Budkowski A, Lekka M. Biophysical and Biochemical Characteristics as Complementary Indicators of Melanoma Progression. Anal Chem 2019; 91:9885-9892. [PMID: 31310097 DOI: 10.1021/acs.analchem.9b01542] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The multistep character of cancer progression makes it difficult to define a unique biomarker of the disease. Interdisciplinary approaches, combining various complementary techniques, especially those operating at a nanoscale level, potentially accelerate characterization of cancer cells or tissue properties. Here, we study a relation between the surface and biomechanical properties of melanoma cells, measured by mass spectrometry (ToF-SIMS) and atomic force microscopy (AFM). In total, seven cell lines have been studied. Six of them were melanoma cells derived from various stages of tumor progression: (1) WM115 cells derived from a 55 year old female skin melanoma at a vertical growth phase (VGP) in the primary melanoma site, (2) WM793 cells established from the vertical growth phase (VGP) of a primary skin melanoma lesion, (3) WM266-4 cells established from a cutaneous skin metastasis detected in the same patient as WM115 cells, (4) WM239 cells derived from a cutaneous skin metastasis, (5) 1205Lu cells originated from a lung metastasis diagnosed in the same patient as WM793 cells, and (6) A375P-cells were derived from a solid malignant tumor located in the lung. As a reference cell line, human epidermal melanocytes from adult skin (primary cell line HEMa-LP) were used. Results reveal low, medium, and large deformability of melanoma cells originating from vertical growth phase (VGP), and skin and lung metastasis, respectively. These changes were accompanied by distinct outcome from principal component analysis (PCA). In relation to VGP melanoma cells, cells from skin and lung metastasis reveal similar or significantly different surface properties. The largest deformability difference observed for cells from VGP and lung metastasis was accompanied by the largest separation of unspecific changes in their surface properties. In this way, we show the evidence that biomechanical and surface biochemical properties of cells change in parallel, indicating a potential of being used as nanobiophysical fingerprints of melanoma progression.
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Affiliation(s)
- Justyna Bobrowska
- Institute of Nuclear Physics , Polish Academy of Sciences , Kraków PL-31341 , Poland
| | - Kamil Awsiuk
- M. Smoluchowski Institute of Physics , Jagiellonian University , Łojasiewicza 11 , Kraków PL-30-348 , Poland
| | - Joanna Pabijan
- Institute of Nuclear Physics , Polish Academy of Sciences , Kraków PL-31341 , Poland
| | - Piotr Bobrowski
- Institute of Metallurgy and Materials , Polish Academy of Sciences , Reymonta 25 , Kraków 30-059 , Poland
| | - Janusz Lekki
- Institute of Nuclear Physics , Polish Academy of Sciences , Kraków PL-31341 , Poland
| | - Katarzyna M Sowa
- M. Smoluchowski Institute of Physics , Jagiellonian University , Łojasiewicza 11 , Kraków PL-30-348 , Poland
| | - Jakub Rysz
- M. Smoluchowski Institute of Physics , Jagiellonian University , Łojasiewicza 11 , Kraków PL-30-348 , Poland
| | - Andrzej Budkowski
- M. Smoluchowski Institute of Physics , Jagiellonian University , Łojasiewicza 11 , Kraków PL-30-348 , Poland
| | - Małgorzata Lekka
- Institute of Nuclear Physics , Polish Academy of Sciences , Kraków PL-31341 , Poland
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Kwiecien I, Bobrowski P, Wierzbicka-Miernik A, Litynska-Dobrzynska L, Wojewoda-Budka J. Growth Kinetics of the Selected Intermetallic Phases in Ni/Al/Ni System with Various Nickel Substrate Microstructure. Nanomaterials (Basel) 2019; 9:nano9020134. [PMID: 30678204 PMCID: PMC6409736 DOI: 10.3390/nano9020134] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 01/18/2019] [Accepted: 01/20/2019] [Indexed: 11/25/2022]
Abstract
Reactivity in nickel–aluminum system was examined for two variants of nickel substrates in terms of the size and shape of Ni grains. The microstructure transformation aroused due to the annealing at 720 °C for different annealing times (0.25 to 72 h) was consequently followed. The sequence of formation of the particular intermetallic phases was given. The interconnection zones were examined by means of scanning electron microscopy supported with energy dispersive X-ray spectroscopy and electron backscattered diffraction techniques as well as by the transmission electron microscopy. The growth kinetics data for AlNi, AlNiNi-rich and AlNi3 phases for both variants of substrates was given, indicating the differences obtained in previous works on this subject.
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Affiliation(s)
- Izabella Kwiecien
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 30-059 Krakow, Poland.
| | - Piotr Bobrowski
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 30-059 Krakow, Poland.
| | - Anna Wierzbicka-Miernik
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 30-059 Krakow, Poland.
| | | | - Joanna Wojewoda-Budka
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 30-059 Krakow, Poland.
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8
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Rogal L, Bobrowski P, Körmann F, Divinski S, Stein F, Grabowski B. Computationally-driven engineering of sublattice ordering in a hexagonal AlHfScTiZr high entropy alloy. Sci Rep 2017; 7:2209. [PMID: 28526830 PMCID: PMC5438366 DOI: 10.1038/s41598-017-02385-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 04/11/2017] [Indexed: 11/24/2022] Open
Abstract
Multi-principle element alloys have enormous potential, but their exploration suffers from the tremendously large range of configurations. In the last decade such alloys have been designed with a focus on random solid solutions. Here we apply an experimentally verified, combined thermodynamic and first-principles design strategy to reverse the traditional approach and to generate a new type of hcp Al-Hf-Sc-Ti-Zr high entropy alloy with a hitherto unique structure. A phase diagram analysis narrows down the large compositional space to a well-defined set of candidates. First-principles calculations demonstrate the energetic preference of an ordered superstructure over the competing disordered solid solutions. The chief ingredient is the Al concentration, which can be tuned to achieve a D019 ordering on the hexagonal lattice. The computationally designed D019 superstructure is experimentally confirmed by transmission electron microscopy and X-ray studies. Our scheme enables the exploration of a new class of high entropy alloys.
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Affiliation(s)
- Lukasz Rogal
- Institute of Metallurgy and Materials Science of the Polish Academy of Sciences, 30-059, Krakow, Poland.
| | - Piotr Bobrowski
- Institute of Metallurgy and Materials Science of the Polish Academy of Sciences, 30-059, Krakow, Poland
| | - Fritz Körmann
- Materials Science and Engineering, Delft University of Technology, 2628, CD, Delft, Netherlands
| | - Sergiy Divinski
- Institute of Materials Physics, University of Münster, Wilhelm-Klemm-Str. 10, 48149, Münster, Germany
| | - Frank Stein
- Max-Planck-Institut für Eisenforschung GmbH D-40237, Düsseldorf, Germany
| | - Blazej Grabowski
- Max-Planck-Institut für Eisenforschung GmbH D-40237, Düsseldorf, Germany.
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Bobrowski P, Pędzich Z, Faryna M. Three-dimensional microstructural characterization of porous cubic zirconia. Micron 2015; 78:73-78. [PMID: 26277084 DOI: 10.1016/j.micron.2015.07.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [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: 04/29/2015] [Revised: 07/17/2015] [Accepted: 07/17/2015] [Indexed: 10/23/2022]
Abstract
A set of cubic zirconia samples were investigated using 3-dimensional electron backscatter diffraction (3D EBSD) to analyze the grain structure, grain boundary networks and pore morphology. 3D EBSD is a variation of conventional EBSD, whereby a focused ion beam (FIB) is used in a dual beam scanning electron microscope (SEM) i.e. FIB-SEM to mill away material and to create 'serial sections' through the material being analyzed. Each new surface revealed is subject to an EBSD scan, which continues sequentially until a desired volume of material has been removed. In this manner, many consecutive 2D EBSD scans can be rendered in 3D to gain a greater insight of microstructural features and parameters. The three samples were examined in order to determine the effect of differences in the manufacturing process used for each. For each sample, a volume of ca. 15,000 μm(3) was studied. The analysis of several microstructure parameters revealed a strong dependence on manufacturing conditions. Subsequently, the results of 3D EBSD analysis were compared to conventional 2D EBSD. Significant differences between the values of microstructure parameters determined by 2D and 3D EBSD were observed.
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Affiliation(s)
- Piotr Bobrowski
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, Krakow, Poland
| | - Zbigniew Pędzich
- Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Krakow, Poland
| | - Marek Faryna
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, Krakow, Poland.
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Sandoval M, Okuhama NN, Zhang XJ, Condezo LA, Lao J, Angeles' FM, Musah RA, Bobrowski P, Miller MJS. Anti-inflammatory and antioxidant activities of cat's claw (Uncaria tomentosa and Uncaria guianensis) are independent of their alkaloid content. Phytomedicine 2002; 9:325-337. [PMID: 12120814 DOI: 10.1078/0944-7113-00117] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Cat's claw is an herbal medicine from the Amazon that is used widely to treat inflammatory disorders. The purpose of this study was to characterize the antioxidative and antiinflammatory properties of cat's claw, Uncaria tomentosa (UT) and Uncaria guianensis (UG). Alkaloids and flavanols were determined using reversed-phase HPLC; scavenging of 1,1-diphenyl-2-picrilhydrazyl (DPPH), hydroxyl radicals, and lipid peroxidation by spectrophotometry; and TNFalpha production by ELISA. Anti-inflammatory activity was assessed in vitro by inhibition of TNFalpha and nitrite production from RAW 264.7 cells exposed to LPS (50 ng/ml) and in vivo using the indomethacin-induced gastritis model. Apoptosis was assessed using the TUNEL technique and TNFalpha mRNA by in situ RT-PCR. In each of the antioxidant assays tested, UG was more potent than UT (P < 0.01). The total oxindole and pentacyclic alkaloid content of UT was 35-fold > UG. The IC50 value for inhibition of TNFalpha production was significantly (P < 0.01) higher for UT (14.1 ng/ml) vs UG (9.5 ng/ml), yet at concentrations that were considerable lower than that required for antioxidant activity. Non-alkaloid HPLC fractions from UT decreased LPS-induced TNFalpha and nitrite production in RAW 264.7 cells (P < 0.01) at a concentration range comparable to the parent botanical. Oral pretreatment for 3 d with UT protected against indomethacin-induced gastritis, and prevented TNFalpha mRNA expression and apoptosis. These results indicate that while both species of cat's claw provide effective antioxidant and anti-inflammatory activities, U. guianensis is more potent. In conclusion, the presence of oxindole or pentacyclic alkaloids did not influence the antioxidant and anti-inflammatory properties of cat's claw.
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Affiliation(s)
- M Sandoval
- Albany Medical College, Center for Cardiovascular Sciences and Deapertment of Pediatrics, NY 12208, USA.
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Miller MJ, MacNaughton WK, Zhang XJ, Thompson JH, Charbonnet RM, Bobrowski P, Lao J, Trentacosti AM, Sandoval M. Treatment of gastric ulcers and diarrhea with the Amazonian herbal medicine sangre de grado. Am J Physiol Gastrointest Liver Physiol 2000; 279:G192-200. [PMID: 10898763 DOI: 10.1152/ajpgi.2000.279.1.g192] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Sangre de grado is an Amazonian herbal medicine used to facilitate the healing of gastric ulcers and to treat gastritis, diarrhea, skin lesions, and insect stings. This study was designed to evaluate the gastrointestinal applications. Gastric ulcers were induced in rats by brief serosal exposure of the fundus to acetic acid (80%). Sangre de grado was administered in drinking water at 1:1,000 and 1:10,000 dilutions from the postoperative period to day 7. Guinea pig ileum secretory responses to capsaicin, electrical field stimulation, and the neurokinin-1 (NK-1) agonist [Sar(9),Met(O(2))(11)]substance P were examined in Ussing chambers. Sangre de grado facilitated the healing of experimental gastric ulcer, reducing myeloperoxidase activity, ulcer size, and bacterial content of the ulcer. The expression of proinflammatory genes tumor necrosis factor-alpha, inducible nitric oxide synthase (iNOS), interleukin (IL)-1beta, IL-6, and cyclooxygenase-2 was upregulated by ulcer induction but reduced by sangre de grado treatment, particularly iNOS and IL-6. In Ussing chambers, sangre de grado impaired the secretory response to capsaicin but not to electrical field stimulation or the NK-1 agonist. We conclude that sangre de grado is a potent, cost-effective treatment for gastrointestinal ulcers and distress via antimicrobial, anti-inflammatory, and sensory afferent-dependent actions.
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Affiliation(s)
- M J Miller
- Department of Pediatrics and Center for Cardiovascular Sciences, Albany Medical College, New York 12208, USA.
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