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1.
Homeopathy ; 110(2): 122-131, 2021 May.
Article in English | MEDLINE | ID: mdl-33694141

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).


Subject(s)
Materia Medica/therapeutic use , Mercury/adverse effects , Pectins/therapeutic use , Plant Growth Regulators/pharmacology , Biological Assay/methods , Materia Medica/standards , Mercury/administration & dosage , Pectins/standards , Plants/drug effects
2.
Homeopathy ; 104(4): 277-82, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26678729

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.


Subject(s)
Biological Assay/methods , Homeopathy/methods , Plant Structures , Biological Assay/statistics & numerical data , Humans , Plant Growth Regulators/pharmacology , Research Design
3.
Homeopathy ; 103(2): 113-26, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24685416

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.


Subject(s)
Araceae/drug effects , Gibberellins/pharmacology , Homeopathy/methods , Plant Growth Regulators/pharmacology , Araceae/growth & development , Biological Assay/methods , Dose-Response Relationship, Drug , Humans , Materia Medica/pharmacology , Reproducibility of Results
4.
Yao Xue Xue Bao ; 46(5): 568-72, 2011 May.
Article in Zh | MEDLINE | ID: mdl-21800546

ABSTRACT

Establishment of bioassay methods is the technical issues to be faced with in the bioassay of Chinese materia medica. Taking the bioassay of Coptis chinensis Franch. as an example, the establishment process and application of the bioassay methods (including bio-potency and bio-activity fingerprint) were explained from the aspects of methodology, principle of selection, experimental design, method confirmation and data analysis. The common technologies were extracted and formed with the above aspects, so as to provide technical support for constructing pattern and method of the quality control for Chinese materia medica based on the dao-di herbs and bioassay.


Subject(s)
Berberine/pharmacology , Biological Assay/methods , Coptis/chemistry , Drugs, Chinese Herbal/standards , Materia Medica/standards , Plants, Medicinal/chemistry , Berberine/isolation & purification , Berberis/chemistry , Cluster Analysis , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacology , Escherichia coli/drug effects , Phellodendron/chemistry , Quality Control
5.
ScientificWorldJournal ; 10: 2112-29, 2010 Nov 04.
Article in English | MEDLINE | ID: mdl-21057725

ABSTRACT

This study evaluated the effects of homeopathically potentized Arsenicum album, nosode, and gibberellic acid in a bioassay with arsenic-stressed duckweed (Lemna gibba L.). The test substances were applied in nine potency levels (17x, 18x, 21x-24x, 28x, 30x, 33x) and compared with controls (unsuccussed and succussed water) regarding their influence on the plant's growth rate. Duckweed was stressed with arsenic(V) for 48 h. Afterwards, plants grew in either potentized substances or water controls for 6 days. Growth rates of frond (leaf) area and frond number were determined with a computerized image analysis system for different time intervals (days 0-2, 2-6, 0-6). Five independent experiments were evaluated for each test substance. Additionally, five water control experiments were analyzed to investigate the stability of the experimental setup (systematic negative control experiments). All experiments were randomized and blinded. The test system exhibited a low coefficient of variation (approximately equal to 1%). Unsuccussed and succussed water did not result in any significant differences in duckweed growth rate. Data from the control and treatment groups were pooled to increase statistical power. Growth rates for days 0-2 were not influenced by any homeopathic preparation. Growth rates for days 2-6 increased after application of potentized Arsenicum album regarding both frond area (p < 0.001) and frond number (p < 0.001), and by application of potentized nosode (frond area growth rate only, p < 0.01). Potencies of gibberellic acid did not influence duckweed growth rate. The systematic negative control experiments did not yield any significant effects. Thus, false-positive results can be excluded with high certainty. To conclude, the test system with L. gibba impaired by arsenic(V) was stable and reliable. It yielded evidence for specific effects of homeopathic Arsenicum album preparations and it will provide a valuable tool for future experiments that aim at revealing the mode of action of homeopathic preparations. It may also be useful to investigate the influence of external factors (e.g., heat, electromagnetic radiation) on the effects of homeopathic preparations.


Subject(s)
Araceae/drug effects , Arsenicals/pharmacology , Gibberellins/pharmacology , Materia Medica/pharmacology , Araceae/growth & development , Arsenic/toxicity , Biological Assay/methods , Dose-Response Relationship, Drug , Homeopathy/methods , Humans , Plant Growth Regulators/pharmacology , Reproducibility of Results
6.
Complement Ther Med ; 40: 13-21, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30219438

ABSTRACT

OBJECTIVES: From a pharmaceutical point of view, we see a need to develop stable preclinical test systems to identify and investigate effects of potentized remedies as used in Anthroposophic Medicine and Homeopathy. We evaluated a plant bioassay regarding its capacity to distinguish homeopathic remedies from placebo, applied as sucrose pillules. METHODS: Pea seed (Pisum sativum L) was soaked for 24 hours in water with dissolved homeopathic or placebo pillules, or in water only. Shoot length was measured 14 days after planting and treatment groups were compared by analysis of variance (ANOVA). The stability of the system was validated by systematic negative control experiments. RESULTS: The system is suitable to test a common application form - sucrose pillules - of a potentized preparation without influence of the pharmaceutical carrier substance. A screening of 13 potentized preparations revealed Calcium carbonicum to affect pea shoot growth (p < 0.05). Three independent series of main experiments were performed with potentized Calcium carbonicum to assess reproducibility. Meta-analysis of all data revealed significant effects of Calcium carbonicum 12c and 30c on pea shoot growth (p < 0.05), which were however dependent on the date of experiment and/or the experimental series. CONCLUSIONS: Potentized Calcium carbonicum, applied as sucrose pillules, influenced pea shoot growth in the assay investigated. However, due to the small effect size and due to the modulation of the effects by still unknown external factors, further optimization of this bioassay is necessary to be used in pharmaceutical quality control or in investigating the biological or pharmaceutical mode of action of potentized preparations.


Subject(s)
Biological Assay/methods , Biological Assay/standards , Calcium Carbonate/pharmacology , Materia Medica/pharmacology , Plant Shoots/drug effects , Analysis of Variance , Pisum sativum/drug effects , Reproducibility of Results , Sucrose/metabolism
7.
J Altern Complement Med ; 17(4): 315-23, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21476829

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.


Subject(s)
Araceae/drug effects , Biological Assay/methods , Homeopathy/methods , Materia Medica/pharmacology , Plant Leaves/drug effects , Stress, Physiological/drug effects , Araceae/growth & development , Arsenic/pharmacology , Color
8.
Homeopathy ; 94(4): 241-7, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16226202

ABSTRACT

We investigated whether water has a 'memory' for succussion compared to unsuccussed controls. The method is based on a bioassay using dinoflagellates. The duration of memory measured by this method is at least 10 min, and may be longer. The effect may be based upon solitons. A hypothesis about the mode of action of homeopathy may be experimentally investigated by this method.


Subject(s)
Biological Assay , Dinoflagellida , Homeopathy/standards , Water , Animals , Biological Assay/methods , Evidence-Based Medicine/standards , Indicator Dilution Techniques/standards , Luminescent Measurements/methods , Materia Medica/standards , Photons , Water/chemistry
10.
São Paulo; s.n; 2000. 220 p. ilus, tab, graf.
Thesis in Portuguese | HomeoIndex (homeopathy) | ID: hom-8134

ABSTRACT

A necessidade de se introduzir novos fármacos quimioterápicos é patente. Para tanto, a modelagem molecular, a terapia gênica e os produtos naturais têm sido os caminhos escolhidos para a obtenção de novas moléculas. As florestas brasileiras estão entre os principais celeiros de biodiversidade, grande parte não estudada do ponto de vista fitoquímico e farmacológico. Isso implica em grandes possibilidades de identificação de novos fármacos, uma vez que a riqueza da biodiversidade biológica pode ser refletida na riqueza da biodiversidade química. Trinta e oito extratos provenientes de espécies de Apocynaceae foram submetidos a um estudo de triagem farmacológica antiviral, antimicrobiana e citotoxicidade, in vitro...(AU)


Subject(s)
Animals , Mice , Plants, Medicinal/toxicity , Pharmacognosy , Plant Extracts/pharmacology , Neoplastic Cells, Circulating/metabolism , Artemia/microbiology , Biological Factors , Cytoprotection/physiology , Maturation-Promoting Factor , Homeopathic Remedy, New , Biological Assay/methods , Chromatography, Thin Layer/methods , Toxic Substances , Culture Media
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