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Roberts ER, Eizayaga JE, van der Werf ET, Tournier AL. HRI Online 2022: Leading International Experts Illustrate the Positive Impact of Increased Collaboration in Homeopathy Research. HOMEOPATHY 2023; 112:65-69. [PMID: 36384231 DOI: 10.1055/s-0042-1757770] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The Homeopathy Research Institute (HRI) welcomed more than 450 people from 35 countries to their first online event on June 25, 2022. The one-day programme featured an excellent line-up of international speakers and provided a unique interactive platform in keeping with the theme of the event - Key Collaborations in Homeopathy Research. Scientists from a range of different research fields gave an exceptional insight into the current status of homeopathy research. Here we give an overview of the most significant findings in both clinical and basic research presented during HRI Online 2022.
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Affiliation(s)
| | - José E Eizayaga
- Department of Homeopathy, Maimónides University, Buenos Aires, Argentina
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Jäger T, Würtenberger S, Baumgartner S. Effects of Homeopathic Preparations of Mercurius corrosivus on the Growth Rate of Moderately Mercury-Stressed Duckweed Lemna gibba L. HOMEOPATHY 2021; 110:122-131. [PMID: 33694141 PMCID: PMC8084595 DOI: 10.1055/s-0040-1718743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background
A bioassay with severely mercury-stressed duckweed (
Lemna gibba
L.) had revealed growth-inhibiting effects of homeopathically potentised mercury(II) chloride (
Mercurius corrosivus, Merc-c.
). We hypothesised that effects of potentised preparations are dependent on the stress level of the organisms used in the bioassay. The aim of the present investigation was to examine the response of duckweed to potentised
Merc-c.
at a lower stress level.
Methods
Duckweed was moderately stressed with 2.5 mg/L mercury(II) chloride for 48 hours. Afterwards plants grew in either
Merc-c.
(seven different potency levels, 24x–30x) or water controls (unsuccussed or succussed water) for 7 days. Growth rates of the frond (leaf) area were determined using a computerised image-analysis system for day 0–3 and 3–7. Three independent experiments with potentised
Merc-c.
and three systematic negative control experiments were performed. All experiments were randomised and blinded.
Results
Unsuccussed and succussed water did not significantly differ in their effects on duckweed growth rate. The systematic negative control experiments did not yield any significant effects, thus providing evidence for the stability of the experimental system. Data from the two control groups and the seven treatment groups (
Merc-c.
24x–30x) were each pooled to increase statistical power. Duckweed growth rates for day 3–7 were enhanced (
p
< 0.05) after application of
Merc-c.
compared with the controls. Growth rates for day 0–3 were not influenced by the homeopathic preparations.
Conclusions
Moderately mercury-stressed
Lemna gibba
L. yielded evidence of growth-enhancing specific effects of
Merc-c.
24x–30x in the second observation period (day 3–7). This observation is complementary to previous experiments with severely mercury-stressed duckweed, in which a decrease in growth was observed in the first observation period (day 0–3). We hypothesise that the differing results are associated with the level of stress intensity (moderate vs. severe).
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Affiliation(s)
- Tim Jäger
- Institute of Integrative Medicine, University of Witten/Herdecke, Witten/Herdecke, Germany
| | - Sandra Würtenberger
- Scientific and Regulatory Affairs, Hevert-Arzneimittel GmbH & Co. KG, Nussbaum, Germany
| | - Stephan Baumgartner
- Institute of Integrative Medicine, University of Witten/Herdecke, Witten/Herdecke, Germany.,Society for Cancer Research, Hiscia Institute, Arlesheim, Switzerland
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Doesburg P, Andersen JO, Scherr C, Baumgartner S. Empirical investigation of preparations produced according to the European Pharmacopoeia monograph 1038. Eur J Pharm Sci 2019; 137:104987. [DOI: 10.1016/j.ejps.2019.104987] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 07/05/2019] [Accepted: 07/06/2019] [Indexed: 11/29/2022]
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Utami D, Kawahata A, Sugawara M, Jog RN, Miwa K, Morikawa M. Effect of Exogenous General Plant Growth Regulators on the Growth of the Duckweed Lemna minor. Front Chem 2018; 6:251. [PMID: 30038905 PMCID: PMC6046615 DOI: 10.3389/fchem.2018.00251] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 06/08/2018] [Indexed: 11/13/2022] Open
Abstract
Gibberellic acid (GA3), indole-3-acetic acid (IAA), salicylic acid (SA), abscidic acid (ABA), jasmonic acid (JA) 1-amino cyclopropane-1-carboxylic acid (ACC) and aminoethoxyvinylglycine (AVG) are popular growth regulators of plants. However, the effects of their exogenous addition on the biomass production of aquatic plants, including Lemnoideae plants, "duckweeds," are largely unknown. In this study, the growth of Lemna minor was tested for 10 d in Hoagland medium containing each compound at different concentrations of 0-50 μM. GA3, IAA, and SA were found to have no apparent positive effect on the growth at all concentrations tested. Conversely, ACC and JA moderately and AVG and ABA severely inhibited the growth of L. minor. Among the tested compounds, ascorbic acid had an apparent growth-promoting effect.
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Affiliation(s)
- Desi Utami
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
| | - Ami Kawahata
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
| | - Masayuki Sugawara
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
| | - Rahul N Jog
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
| | - Kyoko Miwa
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
| | - Masaaki Morikawa
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
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Majewsky V, Scherr C, Schneider C, Arlt SP, Baumgartner S. Reproducibility of the effects of homeopathically potentised Argentum nitricum on the growth of Lemna gibba L. in a randomised and blinded bioassay. HOMEOPATHY 2017; 106:145-154. [PMID: 28844287 DOI: 10.1016/j.homp.2017.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 03/28/2017] [Accepted: 04/06/2017] [Indexed: 11/15/2022]
Abstract
BACKGROUND A previous study reported a significant statistical interaction between experiment date and treatment effect of Argentum nitricum 14x-30x on the growth rate of duckweed (Lemna gibba L.). The aim of the present study was to investigate the stability of the test system and intra-laboratory reproducibility of the effects found. METHODS Duckweed was treated with A. nitricum potencies (14x-30x) as well as succussed and unsuccussed water controls. The outcome parameter area-related growth rate for day 0-7 was determined by a computerised image analysis system in two series of independent randomised and blinded experiments. Systematic negative control (SNC) experiments were carried out to investigate test system stability. Statistical analysis was performed with full two-way analysis of variance (ANOVA) and protected Fisher's Least Significant Difference (LSD) test. RESULTS In the first repetition series we found a significant treatment effect (p = 0.016), while in the second series no effect was observed. The negative control experiments showed that the experimental system was stable. An a posteriori subgroup analysis concerning gibbosity revealed the importance of this growth state of L. gibba for successful reproduction of the statistically significant interaction in the original study; flat: no interaction (p = 0.762); slight gibbosity: no interaction (p = 0.356); medium gibbosity: significant interaction (p = 0.031), high gibbosity: highly significant interaction (p = 0.005). CONCLUSIONS With the original study design (disregarding gibbosity status of L. gibba) results of the original study could not be reproduced sensu stricto. We conclude that the growth state gibbosity is crucial for successful reproduction of the original study. Different physiological states of the test organisms used for bioassays for homeopathic basic research must carefully be considered.
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Affiliation(s)
- Vera Majewsky
- Institute of Complementary Medicine, University of Bern, Fabrikstrasse 8, 3012 Bern, Switzerland; Clinic for Animal Reproduction, Faculty of Veterinary Medicine, Freie Universität Berlin, Königsweg 65 (Haus 27), 14163 Berlin, Germany.
| | - Claudia Scherr
- Institute of Complementary Medicine, University of Bern, Fabrikstrasse 8, 3012 Bern, Switzerland; Hiscia Institute, Society for Cancer Research, Kirschweg 9, 4144 Arlesheim, Switzerland.
| | - Claudia Schneider
- Research Institute of Organic Agriculture FiBL, Ackerstrasse, Postfach, 3070 Frick, Switzerland.
| | - Sebastian Patrick Arlt
- Clinic for Animal Reproduction, Faculty of Veterinary Medicine, Freie Universität Berlin, Königsweg 65 (Haus 27), 14163 Berlin, Germany.
| | - Stephan Baumgartner
- Institute of Complementary Medicine, University of Bern, Fabrikstrasse 8, 3012 Bern, Switzerland; Hiscia Institute, Society for Cancer Research, Kirschweg 9, 4144 Arlesheim, Switzerland; Institute of Integrative Medicine, University of Witten-Herdecke, Gerhard-Kienle-Weg 4, 58313 Herdecke, Germany.
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Kokornaczyk MO, Baumgartner S, Betti L. Polycrystalline structures formed in evaporating droplets as a parameter to test the action of Zincum metallicum 30c in a wheat seed model. HOMEOPATHY 2016; 105:173-9. [DOI: 10.1016/j.homp.2015.10.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 09/30/2015] [Accepted: 10/07/2015] [Indexed: 11/24/2022]
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Jäger T, Scherr C, Shah D, Majewsky V, Wolf U, Betti L, Baumgartner S. The use of plant-based bioassays in homeopathic basic research. HOMEOPATHY 2015; 104:277-82. [PMID: 26678729 DOI: 10.1016/j.homp.2015.06.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 06/09/2015] [Accepted: 06/15/2015] [Indexed: 10/23/2022]
Abstract
OBJECTIVES The objective was to evaluate homeopathic basic research studies that use plant-based bioassays. With this in view, a compilation was made of the findings of three systematic literature reviews covering plant-based bioassays in the three fields of healthy, abiotically, or biotically stressed plants. This compilation focused on investigations using advanced experimental methods and detailed descriptions, also with the aim of supporting the design of future experiments. METHODS Publications included had to report on studies into the effects of homeopathic preparations on whole plants, seeds, plant parts and cells. Outcomes had to be measured by established procedures and statistically evaluated. A Manuscript Information Score (MIS) was applied using predefined criteria to identify publications with sufficient information for adequate interpretation (MIS ≥ 5). Additional evaluation focused on the use of adequate controls to investigate specific effects of homeopathic preparations, and on the use of systematic negative control (SNC) experiments to ensure the stability of the bioassay. Only a fraction of the studies reported here were performed with 'ultra high' dilutions, whereas other studies were performed with moderate or high dilutions. RESULTS A total of 157 publications were identified, describing a total of 167 experimental studies. 84 studies included statistics and 48 had a MIS ≥ 5, thus allowing adequate interpretation. 29 studies had adequate controls to identify specific effects of homeopathic preparations, and reported significant effects of decimal and centesimal homeopathic potencies, including dilution levels beyond Avogadro's number. 10 studies reported use of SNC experiments, yielding evidence for the stability of the experimental set-up. CONCLUSION Plant models appear to be a useful approach for investigating basic research questions relating to homeopathic preparations, but more independent replication trials are needed in order to verify the results found in single experiments. Adequate controls and SNC experiments should be implemented on a routine basis to exclude false-positive results.
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Affiliation(s)
- Tim Jäger
- Institute of Integrative Medicine, University of Witten-Herdecke, Germany; Center for Complementary Medicine, Department of Environmental Health Sciences, Medical Center, University of Freiburg, Germany; Institute of Complementary Medicine IKOM, University of Bern, Switzerland.
| | - Claudia Scherr
- Society for Cancer Research, Hiscia Institute, Arlesheim, Switzerland
| | - Devika Shah
- Society for Cancer Research, Hiscia Institute, Arlesheim, Switzerland
| | - Vera Majewsky
- Clinic for Animal Reproduction, Faculty of Veterinary Medicine, Freie Universität Berlin, Germany
| | - Ursula Wolf
- Institute of Complementary Medicine IKOM, University of Bern, Switzerland
| | - Lucietta Betti
- Department of Agro-Environmental Science and Technology, University of Bologna, Italy
| | - Stephan Baumgartner
- Institute of Integrative Medicine, University of Witten-Herdecke, Germany; Center for Complementary Medicine, Department of Environmental Health Sciences, Medical Center, University of Freiburg, Germany; Society for Cancer Research, Hiscia Institute, Arlesheim, Switzerland
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Majewsky V, Scherr C, Arlt SP, Kiener J, Frrokaj K, Schindler T, Klocke P, Baumgartner S. Reproducibility of effects of homeopathically potentised gibberellic acid on the growth of Lemna gibba L. in a randomised and blinded bioassay. HOMEOPATHY 2014; 103:113-26. [PMID: 24685416 DOI: 10.1016/j.homp.2013.12.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 12/23/2013] [Accepted: 12/23/2013] [Indexed: 11/17/2022]
Abstract
BACKGROUND Reproducibility of basic research investigations in homeopathy is challenging. This study investigated if formerly observed effects of homeopathically potentised gibberellic acid (GA3) on growth of duckweed (Lemna gibba L.) were reproducible. METHODS Duckweed was grown in potencies (14x-30x) of GA3 and one time succussed and unsuccussed water controls. Outcome parameter area-related growth rate was determined by a computerised image analysis system. Three series including five independent blinded and randomised potency experiments (PE) each were carried out. System stability was controlled by three series of five systematic negative control (SNC) experiments. Gibbosity (a specific growth state of L. gibba) was investigated as possibly essential factor for reactivity of L. gibba towards potentised GA3 in one series of potency and SNC experiments, respectively. RESULTS Only in the third series with gibbous L. gibba L. we observed a significant effect (p = 0.009, F-test) of the homeopathic treatment. However, growth rate increased in contrast to the former study, and most biologically active potency levels differed. Variability in PE was lower than in SNC experiments. The stability of the experimental system was verified by the SNC experiments. CONCLUSIONS Gibbosity seems to be a necessary condition for reactivity of L. gibba to potentised GA3. Further still unknown conditions seem to govern effect direction and the pattern of active and inactive potency levels. When designing new reproducibility studies, the physiological state of the test organism must be considered. Variability might be an interesting parameter to investigate effects of homeopathic remedies in basic research.
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Affiliation(s)
- Vera Majewsky
- Institute of Complementary Medicine, University of Berne, Insel-Spital, Imhoof-Pavillon, 3010 Bern, Switzerland; Clinic for Animal Reproduction, Faculty of Veterinary Medicine, Freie Universität Berlin, Königsweg 65 (Haus 27, Gebäude 19), 14163 Berlin, Germany; Research Institute of Organic Agriculture FiBL, Ackerstrasse, Postfach, 3070 Frick, Switzerland.
| | - Claudia Scherr
- Institute of Complementary Medicine, University of Berne, Insel-Spital, Imhoof-Pavillon, 3010 Bern, Switzerland; Hiscia Institute, Society for Cancer Research, Kirschweg 9, 4144 Arlesheim, Switzerland
| | - Sebastian Patrick Arlt
- Clinic for Animal Reproduction, Faculty of Veterinary Medicine, Freie Universität Berlin, Königsweg 65 (Haus 27, Gebäude 19), 14163 Berlin, Germany
| | - Jonas Kiener
- Research Institute of Organic Agriculture FiBL, Ackerstrasse, Postfach, 3070 Frick, Switzerland
| | - Kristina Frrokaj
- Research Institute of Organic Agriculture FiBL, Ackerstrasse, Postfach, 3070 Frick, Switzerland
| | - Tobias Schindler
- Research Institute of Organic Agriculture FiBL, Ackerstrasse, Postfach, 3070 Frick, Switzerland
| | - Peter Klocke
- Research Institute of Organic Agriculture FiBL, Ackerstrasse, Postfach, 3070 Frick, Switzerland; Bovicare GmbH, Hermannswerder Haus 14, 14473 Potsdam, Germany
| | - Stephan Baumgartner
- Institute of Complementary Medicine, University of Berne, Insel-Spital, Imhoof-Pavillon, 3010 Bern, Switzerland; Hiscia Institute, Society for Cancer Research, Kirschweg 9, 4144 Arlesheim, Switzerland; Institute of Integrative Medicine, University of Witten-Herdecke, Gerhard-Kienle-Weg 4, 58313 Herdecke, Germany
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Jäger T, Scherr C, Simon M, Heusser P, Baumgartner S. Development of a test system for homeopathic preparations using impaired duckweed (Lemna gibba L.). J Altern Complement Med 2011; 17:315-23. [PMID: 21476829 DOI: 10.1089/acm.2010.0246] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
OBJECTIVES A bioassay with arsenic-stressed duckweed (Lemna gibba L.) was developed to study potentially regulative effects of homeopathic preparations. We compared potentized substances (nine different potency levels between 17 x and 33 x ) with two controls (unsuccussed and succussed water) regarding their influence on number- and area-related growth rate and color of fronds (leaves). Screening included 11 potentized substances: Arsenicum album, gibberellic acid, nosode, arsenic(V), phosphorus, Conchae, Acidum picrinicum, Argentum nitricum, Crotalus horridus, Hepar sulfuris, and Mercurius vivus naturalis. DESIGN Duckweed was stressed with arsenic(V) for 48 hours. Afterwards, plants grew in either potentized substances or water controls for 6 days. Growth rate and color of fronds were determined with a computerized image analysis system for different time intervals (days 0-2, 2-6, 0-6). A systematic negative control experiment with unsuccussed water was used to investigate the stability of the bioassay. All experiments were randomized and blinded. RESULTS Arsenicum album and nosode potencies increased frond number-related growth rate compared to controls (succussed water controls or pooled water controls [succussed and unsuccussed], p < 0.05, t test). Regarding color classification, no effects were observed. CONCLUSIONS The experimental setup with L. gibba stressed by arsenic(V) provides a valuable tool to investigate regulative effects of potentized substances. In order to verify the effects of Arsenicum album and nosode potencies, further independent replication experiments are necessary.
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Affiliation(s)
- Tim Jäger
- Institute of Complementary Medicine KIKOM, University of Bern, Switzerland.
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Use of homeopathic preparations in experimental studies with healthy plants. HOMEOPATHY 2009; 98:228-43. [DOI: 10.1016/j.homp.2009.09.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 09/14/2009] [Accepted: 09/24/2009] [Indexed: 11/18/2022]
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Scherr C, Simon M, Spranger J, Baumgartner S. Effects of potentised substances on growth rate of the water plant Lemna gibba L. Complement Ther Med 2009; 17:63-70. [PMID: 19185263 DOI: 10.1016/j.ctim.2008.10.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2007] [Revised: 08/22/2008] [Accepted: 10/28/2008] [Indexed: 01/30/2023] Open
Abstract
OBJECTIVES This study investigated, whether the growth rate of Lemna gibba L. (duckweed) can be influenced by the application of homeopathic potencies of gibberellic acid, kinetin, argentum nitricum, and lemna minor. METHODS Duckweed was grown in either potencies (14x-30x, decimal steps) or water controls (unsuccussed and succussed) over seven days. Frond (leaf-like structure) growth was measured using a non-destructive image analysis system. Growth rates were calculated for three time intervals (0-7, 0-3, 3-7 days). Five to six independent, randomized and blinded experiments were analysed for each of the four tested substances. Water control experiments were performed repeatedly to test the reliability of the experimental set-up (systematic negative controls). RESULTS The systematic negative control experiments did not yield any significant effects. Hence, false positive results could be excluded. The test system had a low coefficient of variation (1.5%). Out of the four tested substances gibberellic acid had the most pronounced effect (p=0.0002, F-test) on the main outcome parameter frond growth rate (r(area) day 0-7). Potency levels 15x, 17x, 18x, 23x and 24x reduced growth rate of Lemna gibba (p<0.05 against the pooled water control, LSD test). CONCLUSIONS Lemna gibba may be considered as a suitable test organism for further studies on the efficacy of homeopathic potencies. Evidence accumulates, that adjacent potency levels may strongly differ in their biological activity. Potential consequences for therapeutical application might be worth investigating.
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Affiliation(s)
- Claudia Scherr
- Research Institute of Organic Agriculture (FiBL), Ackerstrasse, Frick, Switzerland.
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Scherr C, Simon M, Spranger J, Baumgartner S. Test system stability and natural variability of a Lemna gibba L. bioassay. PLoS One 2008; 3:e3133. [PMID: 18769541 PMCID: PMC2518950 DOI: 10.1371/journal.pone.0003133] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2008] [Accepted: 07/31/2008] [Indexed: 01/03/2023] Open
Abstract
Background In ecotoxicological and environmental studies Lemna spp. are used as test organisms due to their small size, rapid predominantly vegetative reproduction, easy handling and high sensitivity to various chemicals. However, there is not much information available concerning spatial and temporal stability of experimental set-ups used for Lemna bioassays, though this is essential for interpretation and reliability of results. We therefore investigated stability and natural variability of a Lemna gibba bioassay assessing area-related and frond number-related growth rates under controlled laboratory conditions over about one year. Methology/Principal Findings Lemna gibba L. was grown in beakers with Steinberg medium for one week. Area-related and frond number-related growth rates (r(area) and r(num)) were determined with a non-destructive image processing system. To assess inter-experimental stability, 35 independent experiments were performed with 10 beakers each in the course of one year. We observed changes in growth rates by a factor of two over time. These did not correlate well with temperature or relative humidity in the growth chamber. In order to assess intra-experimental stability, we analysed six systematic negative control experiments (nontoxicant tests) with 96 replicate beakers each. Evaluation showed that the chosen experimental set-up was stable and did not produce false positive results. The coefficient of variation was lower for r(area) (2.99%) than for r(num) (4.27%). Conclusions/Significance It is hypothesised that the variations in growth rates over time under controlled conditions are partly due to endogenic periodicities in Lemna gibba. The relevance of these variations for toxicity investigations should be investigated more closely. Area-related growth rate seems to be more precise as non-destructive calculation parameter than number-related growth rate. Furthermore, we propose two new validity criteria for Lemna gibba bioassays: variability of average specific and section-by-section segmented growth rate, complementary to average specific growth rate as the only validity criterion existing in guidelines for duckweed bioassays.
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Affiliation(s)
- Claudia Scherr
- Research Institute of Organic Agriculture, Frick, Switzerland.
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Baumgartner S, Shah D, Schaller J, Kämpfer U, Thurneysen A, Heusser P. Reproducibility of dwarf pea shoot growth stimulation by homeopathic potencies of gibberellic acid. Complement Ther Med 2008; 16:183-91. [PMID: 18638708 DOI: 10.1016/j.ctim.2008.03.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Revised: 02/01/2008] [Accepted: 03/06/2008] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES Investigation of the conditions for reproducibility of dwarf pea shoot growth stimulation through homeopathic potencies of gibberellic acid. METHODS 4 batches of pea seed (Pisum sativum L. cv. Früher Zwerg; harvests from 1997, 1998, 1999, and 2000) were tested regarding their reaction to gibberellic acid 17x and 18x (compared to unsuccussed and succussed water (1x) as controls) in 8 independent randomized and blinded experiments. Pea seed was immersed for 24h in watery solutions of homeopathic potencies or controls, and cultivated under controlled laboratory conditions. Pea shoot length was measured after 14 days. Two systematic negative control experiments assessed the stability of the experimental set-up. RESULTS The systematic negative control experiments yielded no significant effects and confirmed the stability of the experimental set-up. 2 out of 4 seed batches reacted to the homeopathic treatment (p<0.05). Seed batch 1997 showed a reproducible reaction to gibberellic acid 17x (shoot length stimulation of +11.2%, p=0.007), and seed batch 1998 showed a significant varying response (increase/decrease). Seed batch 1997 differed from the other 3 batches by an increased glucose and fructose content, and reduced 1000kernel weight. Meta-analysis with data of earlier experiments is in accordance with the results of the present experimental series. CONCLUSIONS We identified 'seed quality' as a possible trigger factor for successful reproducibility in homeopathic basic research. Premature harvesting as a possible key factor for responsiveness of dwarf peas to homeopathic potencies of gibberellic acid is our current working hypothesis to be tested in future experiments.
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Affiliation(s)
- Stephan Baumgartner
- Institute of Complementary Medicine KIKOM, University of Bern, Bern, Switzerland.
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