Multidimensional Outcome Parameters in a Cress Seedling-CuCl2 Crystallization Assay to Corroborate Specific Effects of Stannum metallicum 30x Compared to Lactose 30x.

BACKGROUND: Previously we developed a test system which yielded highly significant evidence for specific effects of a Stannum metallicum 30x preparation in a multi-center replication trial. This test system is based on cress seed germination in homeopathic or control samples, CuCl2 crystallization of the cress extract, and subsequent digital textural image analysis of the resulting crystallization patterns. OBJECTIVES: The current study aimed to investigate whether three novel outcome parameters could further corroborate and possibly characterize the specific effects of Stannum metallicum 30x. METHODS: To this end, (1) cress seedling length, (2) a second texture analysis parameter, entropy and (3) the local connected fractal dimension (LCFD) of crystallization patterns as a measure of complexity were considered. The stability of the experimental setup was monitored throughout the entire investigation with systematic negative control (SNC) experiments. RESULTS: Cress length and entropy revealed a time-modulated potency treatment effect, in the absence of a significant main treatment effect. This indicated that the effect of the potency treatment varied significantly across the different experimental days. LCFD yielded a highly significant potency treatment effect. In addition, a significant interaction of treatment with experimental day seems to indicate a modulation of this effect. No significant effects were observed in any of the evaluations of the SNC experiments, indicative of a stable experimental setup and a reliable and specific treatment effect. Neither significant nor strong correlations were found between the four parameters, indicating that they reflect different effects of Stannum metallicum 30x on the organism treated. CONCLUSION: This quadruple characterization of the biological effects of Stannum metallicum 30x provides an unprecedented opportunity for basic homeopathy research into, among others, the presumed specificity of homeopathic preparations.

Self-assembled Patterns Formed in Evaporating Droplets to Analyze Bi-component Homeopathic Preparations in the Low Dilution Range.

BACKGROUND: Homeopathic complex remedies, composed of several homeopathic medicines in the low potency range, are frequently used in the treatment of a number of common disorders. At the same time, they represent an almost unexplored area of research. Are complex remedies just additive mixtures of the components, or are there interactions between the latter leading to new properties of the complex? METHODS: In the present study, we analyzed as an example the simple bi-component complex, Luffa 4x - Mercurius bijodatus 9x, by means of patterns from evaporated droplets and tested what influences the complex's single compounds have upon the patterns and if there are any interactions. For this purpose, we compared in a series of five experiments patterns from evaporated droplets of the complex, Luffa 4x - Mercurius bijodatus 9x, and three comparison samples in which one or both of the complex's compounds were replaced by potentized solute. The patterns were photographed and evaluated for their gray-level distribution and texture using the software ImageJ. The experimental set-up's stability was tested by means of systematic control experiments. RESULTS: We found that Mercurius bijodatus 9x significantly influenced the patterns of Luffa 4x, increasing their homogeneity; at the same time, the patterns of Mercurius bijodatus 9x combined with solvent were more heterogeneous than those obtained from a control consisting of two pure solvents. CONCLUSION: In this phenomenological assay, the complex Luffa 4x - Mercurius bijodatus 9x does not correspond to a simple addition of the components. The exact nature of the underlying interaction needs to be elucidated in further investigations.

Cancer-related fatigue in patients treated with mistletoe extracts: a systematic review and meta-analysis.

PURPOSE: Cancer-related fatigue remains one of the most prevalent and distressing symptoms experienced by cancer patients. Effective treatments for cancer-related fatigue are needed. The objective of this meta-analysis is to determine the impact of mistletoe extracts as a pharmacological treatment for the management of cancer-related fatigue. METHODS: We included randomized clinical trials (RCTs) and non-randomized studies of interventions (NRSIs) in cancer patients. Inclusion criteria were cancer-related fatigue severity or prevalence as an outcome and testing of mistletoe extracts compared to control groups. We searched Medline (EuropePMC), Embase, the Cochrane Central Register of Controlled Trials, Clinicaltrials.gov, and opengrey.org through October 2020. We assessed the risk of bias using the Cochrane risk of bias tools for RCTs and NRSIs and conducted a meta-analysis. RESULTS: We performed one meta-analysis with 12 RCTs, including 1494 participants, and one meta-analysis with seven retrospective NRSIs, including 2668 participants. Heterogeneity between the studies was high in both meta-analyses. Most studies had a high risk of bias. A random-effects model showed for RCTs a standardized mean difference of -0.48 (95% confidence interval -0.82 to -0.14; p = 0.006) and for NRSIs an odds ratio of 0.36 (95% confidence interval 0.20 to 0.66; p = 0.0008). CONCLUSION: Treatment with mistletoe extracts shows a moderate effect on cancer-related fatigue of similar size to physical activity. These results need to be confirmed by more placebo-controlled trials. Future trials should investigate different treatment durations and their effect on cancer-related fatigue in post-treatment cancer survivors. TRIAL REGISTRATION: This meta-analysis has been registered under the PROSPERO registration number CRD42020191967 on October 7, 2020.

In vitro evaluation of the anti-pathogenic activity of Okoubaka aubrevillei on the human gastrointestinal tract.

BACKGROUND: Okoubaka aubrevillei is used in traditional West African medicine and in homeopathy for treatment and prevention of several gastrointestinal problems. The aim of this in vitro study was to evaluate the effect of repeated doses of two Okoubaka products (10 % ethanolic tincture, mother tincture (MT); 3rd decimal potency, 3X) on the microbial activity of physiological human colon microbiota using a Simulator of the Human Intestinal Microbial Ecosystem (SHIME®) and to investigate any preventive effect against infections with diarrhea-causing pathogens. METHODS: Upon inoculation with fecal microbiota from a healthy donor, 4 parallel proximal colon compartments of the SHIME were treated either with Okoubaka MT, Okoubaka 3X, ethanol control or blank control for 7 days. Using the Okoubaka-adapted microbial community from SHIME, 48 h challenge tests were performed with enterotoxigenic Escherichia coli (ETEC) and Salmonella enteritidis in 4 different doses (103-108 colony forming units as typical in vivo infectious doses). Pathogen concentrations, short-chain fatty acids (SCFAs) and branched SCFA production were measured in triplicate at 0, 24 and 48 h. RESULTS: In the challenge tests, both Okoubaka products were able to restrict the colonization of ETEC and Salmonella at 3 of the 4 pathogen doses (except the highest doses), with a stronger anti-pathogenic effect for MT, which included a reduction of 2.0 log-units of ETEC (p < 0.0001) and 1.1 log-units of Salmonella (p < 0.0001). Total SCFA levels remained unaffected, but butyrate increased during the first 24 h (p < 0.0001 for ETEC), accompanied by decreased acetate production. CONCLUSION: We observed in vitro a systemic activating effect of Okoubaka on intestinal microbiome resistance, which resulted in an anti-pathogenic effect, especially against ETEC. We hypothesize that the mode of action in vivo is also based on systemic regulative effects.

Effects of Homeopathic Preparations of Mercurius corrosivus on the Growth Rate of Moderately Mercury-Stressed Duckweed Lemna gibba L.

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).

Comprehensive Metabolome Analysis of Fermented Aqueous Extracts of Viscum album L. by Liquid Chromatography-High Resolution Tandem Mass Spectrometry.

Fermented aqueous extracts of Viscum album L. are widely used for cancer treatment in complementary medicine. The high molecular weight compounds viscotoxins and lectins are considered to be the main active substances in the extracts. However, a vast number of small molecules (≤1500 Da) is also expected to be present, and few studies have investigated their identities. In this study, a comprehensive metabolome analysis of samples of fermented aqueous extracts of V. album from two host tree species (Malus domestica and Pinus sylvestris), both prepared by two pharmaceutical manufacturing processes, was performed by liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS). A total of 212 metabolites were putatively annotated, including primary metabolites (e.g., amino acids, organic acids, etc.) and secondary metabolites (mostly phenolic compounds). A clear separation between V. album samples according to the host tree species, but not due to manufacturing processes, was observed by principal component analysis. The biomarkers responsible for this discrimination were assessed by partial least squares-discriminant analysis. Because V. album extracts from different host trees have different clinical applications, the present work highlights the possibility of characterizing the metabolome for identification and traceability of V. album fermented aqueous extracts.

Estrogen-dependent control and cell-to-cell variability of transcriptional bursting.

Cellular decision-making and environmental adaptation are dependent upon a heterogeneous response of gene expression to external cues. Heterogeneity arises in transcription from random switching between transcriptionally active and inactive states, resulting in bursts of RNA synthesis. Furthermore, the cellular state influences the competency of transcription, thereby globally affecting gene expression in a cell-specific manner. We determined how external stimuli interplay with cellular state to modulate the kinetics of bursting. To this end, single-cell dynamics of nascent transcripts were monitored at the endogenous estrogen-responsive GREB1 locus. Stochastic modeling of gene expression implicated a two-state promoter model in which the estrogen stimulus modulates the frequency of transcriptional bursting. The cellular state affects transcriptional dynamics by altering initiation and elongation kinetics and acts globally, as GREB1 alleles in the same cell correlate in their transcriptional output. Our results suggest that cellular state strongly affects the first step of the central dogma of gene expression, to promote heterogeneity in the transcriptional output of isogenic cells.

Effects of Homeopathic Preparations of Mercurius corrosivus on the Growth Rate of Severely Mercury-Stressed Duckweed Lemna gibba L.

BACKGROUND: We developed a bioassay with mercury-stressed duckweed (Lemna gibba L.) to study potential effects of homeopathically potentised mercury(II) chloride (Mercurius corrosivus [Merc-c.]). The response of this bioassay to homeopathic treatments as a function of stress intensity was also of interest. METHODS: Duckweed was severely stressed with mercury(II) chloride for 48 hours. Afterwards plants grew in either Merc-c. (seven different potency levels, 24x to 30x) or water controls (unsuccussed and succussed water) for 7 days. Growth rates of the frond (leaf) area were determined using a computerised image analysis system for different time intervals between the measurements on days 0, 3 and 7. Three independent experiments with potentised Merc-c. each were evaluated. Additionally, three water control experiments were analysed to investigate the stability of the experimental set-up (systematic negative control [SNC] experiments). All experiments were randomised and blinded. RESULTS: Unsuccussed and succussed water did not significantly differ in terms of duckweed growth rate. The SNC experiments did not yield any significant effects, 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 the statistical power. Duckweed growth rates for day 0 to 3 were reduced (p < 0.05) after application of Merc-c. compared with the controls. Growth rates for day 3 to 7 were not influenced by the homeopathic preparations. CONCLUSIONS: The present test system with Lemna gibba L. that was severely stressed by mercury yielded evidence for specific effects of Merc-c. 24x to 30x, namely a growth reduction in the first time period (day 0-3). This is in contrast to former experiments with slightly arsenic-stressed duckweed, where a growth increase was observed in the second time period (day 2-6). We hypothesise that the differing results are associated with the level of stress intensity (severe versus slight).

Phenomenological Characterization of Low-Potency Homeopathic Preparations by Means of Pattern Formation in Evaporating Droplets.

BACKGROUND: Evaporation-induced pattern formation in droplets has been applied to test effects of high potencies. Here we propose for the first time the droplet evaporation method (DEM) as a tool to characterize low potencies on a qualitative and quantitative basis. MATERIALS AND METHODS: The present investigation consisted of: (1) screening of 18 different substances of mineral, vegetal, and animal origin in the 1x to 6x potency range; choice of four substances with characteristic pattern-forming properties; (2) replication experiments aiming at the differentiation of four homeopathic preparations at the same potency levels (2x-6x); and (3) control experiments performed on three preparations. The DEM experimental protocol consisted of the evaporation of droplets of the analyzed potency per se, placed on microscope slides and in controlled conditions. The resulting patterns were photographed and subjected to computerized image analysis. RESULTS: The screening experiments yielded a wide variety of patterns. Homeopathic preparations of mineral origin showed the largest variety of forms, whereas potencies of vegetal origin mostly created dendritic patterns, probably due to diffusion-limited aggregation. The here-analyzed image analysis variables (gray-level distribution, entropy, and inverse difference moment) allowed a highly significant differentiation of patterns prepared from four substances (Echinacea, Baptisia, Luffa, and Spongia) at the same potency levels in the range 2x to 4x, whereas patterns obtained from potencies 5x and 6x could no longer be differentiated and resembled the pattern of pure solute (purified water). The control experiments showed reasonable experimental model stability. CONCLUSIONS: DEM seems to be a promising tool for qualitative phenomenological characterization of homeopathic preparations in low potency. We propose the application of the current experimental model for investigating further research topics in this field, such as the comparison of potencies versus simple dilutions or the contribution of component remedies to the patterns formed by homeopathic combination medicines.

Phase-Transition-Induced Pattern Formation Applied to Basic Research on Homeopathy: A Systematic Review.

BACKGROUND: Methods based on phase-transition-induced pattern formation (PTPF) are increasingly used in medical research. Frequent application fields are medical diagnosis and basic research in homeopathy. Here, we present a systematic review of experimental studies concerning PTPF-based methods applied to homeopathy research. We also aimed at categorizing the PTPF methods included in this review. MATERIALS AND METHODS: Experimental studies were collected from scientific databases (PubMed, Web of Science, Russian eLibrary) and from experts in the research field in question, following the PRISMA guidelines. The studies were rated according to pre-defined scientific criteria. RESULTS: The review included 15 experimental studies. We identified seven different PTPF methods applied in 12 experimental models. Among these methods, phase-transition was triggered through evaporation, freezing, or solution, and in most cases led to the formation of crystals. First experimental studies concerning the application of PTPF methods in homeopathic research were performed in the first half of the 20th century; however, they were not continued in the following years. Only in the last decade, different research groups re-launched the idea, introducing new experimental approaches and computerized pattern evaluation techniques. The here-identified PTPF methods are for the first time proposed to be classified as one group of methods based on the same basic physical phenomenon. CONCLUSIONS: Although the number of experimental studies in the area is still rather limited, the long tradition in the application of PTPF methods and the dynamics of the present developments point out the high potential of these methods and indicate that they might meet the demand for scientific methods to study potentized preparations.

Systematic Review of Plant-Based Homeopathic Basic Research: An Update.

BACKGROUND: Plant-based test systems have been described as a useful tool for investigating possible effects of homeopathic preparations. The last reviews of this research field were published in 2009/2011. Due to recent developments in the field, an update is warranted. Publications on plant-based test systems were analysed with regard to publication quality, reproducibility and potential for further research. METHODS: A literature search was conducted in online databases and specific journals, including publications from 2008 to 2017 dealing with plant-based test systems in homeopathic basic research. To be included, they had to contain statistical analysis and fulfil quality criteria according to a pre-defined manuscript information score (MIS). Publications scoring at least 5 points (maximum 10 points) were assumed to be adequate. They were analysed for the use of adequate controls, outcome and reproducibility. RESULTS: Seventy-four publications on plant-based test systems were found. Thirty-nine publications were either abstracts or proceedings of conferences and were excluded. From the remaining 35 publications, 26 reached a score of 5 or higher in the MIS. Adequate controls were used in 13 of these publications. All of them described specific effects of homeopathic preparations. The publication quality still varied: a substantial number of publications (23%) did not adequately document the methods used. Four reported on replication trials. One replication trial found effects of homeopathic preparations comparable to the original study. Three replication trials failed to confirm the original study but identified possible external influencing factors. Five publications described novel plant-based test systems. Eight trials used systematic negative control experiments to document test system stability. CONCLUSIONS: Regarding research design, future trials should implement adequate controls to identify specific effects of homeopathic preparations and include systematic negative control experiments. Further external and internal replication trials, and control of influencing factors, are needed to verify results. Standardised test systems should be developed.

Reproducibility of the effects of homeopathically potentised Argentum nitricum on the growth of Lemna gibba L. in a randomised and blinded bioassay.

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.

Model validity of randomised placebo-controlled trials of non-individualised homeopathic treatment.

BACKGROUND: The comprehensive systematic review of randomised placebo-controlled trials (RCTs) in homeopathy requires examination of a study's model validity of homeopathic treatment (MVHT) as well as its risk of bias (extent of reliable evidence). OBJECTIVE: To appraise MVHT in those RCTs of non-individualised homeopathy that an associated investigation had judged as 'not at high risk of bias'. DESIGN: Systematic review. METHODS: An assessment of MVHT was ascribed to each of 26 eligible RCTs. Another 49 RCTs were ineligible due to their high risk of bias. MAIN OUTCOME MEASURES: MVHT and the prior risk of bias rating per trial were merged to obtain a single overall quality designation ('high', 'moderate', 'low'), based on the GRADE principle of downgrading. RESULTS: The trials were rated as 'acceptable MVHT' (N = 9), 'uncertain MVHT' (N = 10) and 'inadequate MVHT' (N = 7); and, previously, as 'reliable evidence' (N = 3) and 'non-reliable evidence' (N = 23). The 26 trials were designated overall as: 'high quality' (N = 1); 'moderate quality' (N = 18); 'low quality' (N = 7). CONCLUSION: Of the 26 RCTs of non-individualised homeopathy that were judged 'not at high risk of bias', nine have been rated 'acceptable MVHT'. One of those nine studies was designated 'high quality' overall ('acceptable MVHT' and 'reliable evidence'), and is thus currently the only reported RCT that represents best therapeutic practice as well as unbiased evidence in non-individualised homeopathy. As well as minimising risk of bias, new RCTs in this area must aim to maximise MVHT and clarity of reporting.

Polycrystalline structures formed in evaporating droplets as a parameter to test the action of Zincum metallicum 30c in a wheat seed model.

BACKGROUND: Polycrystalline structures formed inside evaporating droplets of different biological fluids have been shown sensitive towards various influences, including ultra high dilutions (UHDs), representing so a new approach potentially useful for basic research in homeopathy. In the present study we tested on a wheat seed model Zincum metallicum 30c efficacy versus lactose 30c and water. MATERIALS AND METHODS: Stressed and non-stressed wheat seeds were watered with the three treatments. Seed-leakage droplets were evaporated and the polycrystalline structures formed inside the droplet residues were analyzed for their local connected fractal dimensions (LCFDs) (measure of complexity) using the software ImageJ. RESULTS: We have found significant differences in LCFD values of polycrystalline structures obtained from stressed seeds following the treatments (p<0.0001); Zincum metallicum 30c lowered the structures' complexity compared to lactose 30c and water. In non-stressed seeds no significant differences were found. CONCLUSIONS: The droplet evaporation method (DEM) might represent a potentially useful tool in basic research in homeopathy. Furthermore our results suggest a sensitization of the stressed model towards the treatment action, which is conforming to previous findings.

Tumour cell derived effects on monocyte/macrophage polarization and function and modulatory potential of Viscum album lipophilic extract in vitro.

BACKGROUND: Macrophages are highly versatile cells that play an important role in tumour microenvironment. Tumour associated macrophages (TAMs) have been linked to both, good or bad prognosis of several cancer types depending on their number, composition and polarization. Viscum album lipophilic extract (VALE) contains several pentacyclic triterpenes known to modulate the activity of monocytes and other immune cells and to exhibit anticancer properties. In our in vitro study, we investigated the effect of tumour cell lines on macrophage polarization and monocyte chemotactic transmigration and examined the modulatory potential of VALE and its predominant triterpene oleanolic acid (OA). METHODS: Human peripheral blood monocytes were differentiated into monocyte derived macrophages (MDM) using M-CSF and polarized into M1 by IFN-γ and LPS and into M2 macrophages by IL-4 and IL-13 or by co-culture with two different tumour cell lines. Polarized macrophages were subsequently treated with VALE or OA. Phenotypic markers and cytokines were assessed by flow cytometry and immunoanalysis. Migration of human peripheral blood monocytes induced by monocyte chemotactic protein-1 (MCP-1) or supernatants of different tumour cell lines under the influence of VALE or OA was measured in a chemotaxis transmigration assay. RESULTS: In vitro polarized M1 and M2 type macrophages revealed specific phenotypic patterns and tumour cell co-cultured MDM displayed ambiguous phenotypes with M1 as well as M2 associated markers. VALE and OA showed modest influence on cell surface marker profile and cytokine expression of tumour cell co-cultured macrophages. All tumour cell supernatants markedly enhanced the migratory activity of monocytes. VALE and OA significantly inhibited MCP-1 induced monocyte transmigration, whereas monocyte migration initiated by tumour cell derived supernatants was not affected. CONCLUSIONS: In our study we reconfirmed that co-culture with different tumour cell lines can result in a mixed macrophage phenotype with M1 as well as M2 patterns, a finding that is important for a better understanding of tumour microenvironment functions. Moreover, we demonstrated that VALE shows slight immunomodulatory effects on tumour cell co-cultured macrophages and modulates monocyte chemotactic transmigration in vitro, indicating promising possibilities of triterpenes from Viscum album L. to contribute in a multimodal concept of anti-cancer therapy in future. Our data contribute to an understanding of monocyte function and macrophage polarization in vitro and of the possibility to influence their behaviour by triterpene containing mistletoe extracts.

The use of plant-based bioassays in homeopathic basic research.

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.

Determinants of cell-to-cell variability in protein kinase signaling.

Cells reliably sense environmental changes despite internal and external fluctuations, but the mechanisms underlying robustness remain unclear. We analyzed how fluctuations in signaling protein concentrations give rise to cell-to-cell variability in protein kinase signaling using analytical theory and numerical simulations. We characterized the dose-response behavior of signaling cascades by calculating the stimulus level at which a pathway responds ('pathway sensitivity') and the maximal activation level upon strong stimulation. Minimal kinase cascades with gradual dose-response behavior show strong variability, because the pathway sensitivity and the maximal activation level cannot be simultaneously invariant. Negative feedback regulation resolves this trade-off and coordinately reduces fluctuations in the pathway sensitivity and maximal activation. Feedbacks acting at different levels in the cascade control different aspects of the dose-response curve, thereby synergistically reducing the variability. We also investigated more complex, ultrasensitive signaling cascades capable of switch-like decision making, and found that these can be inherently robust to protein concentration fluctuations. We describe how the cell-to-cell variability of ultrasensitive signaling systems can be actively regulated, e.g., by altering the expression of phosphatase(s) or by feedback/feedforward loops. Our calculations reveal that slow transcriptional negative feedback loops allow for variability suppression while maintaining switch-like decision making. Taken together, we describe design principles of signaling cascades that promote robustness. Our results may explain why certain signaling cascades like the yeast pheromone pathway show switch-like decision making with little cell-to-cell variability.

Interaction of standardized mistletoe (Viscum album) extracts with chemotherapeutic drugs regarding cytostatic and cytotoxic effects in vitro.

BACKGROUND: Given the importance of complementary and alternative medicine (CAM) to cancer patients, there is an increasing need to learn more about possible interactions between CAM and anticancer drugs. Mistletoe (Viscum album L.) belongs to the medicinal herbs that are used as supportive care during chemotherapy. In the in vitro study presented here the effect of standardized mistletoe preparations on the cytostatic and cytotoxic activity of several common conventional chemotherapeutic drugs was investigated using different cancer cell lines. METHODS: Human breast carcinoma cell lines HCC1937 and HCC1143 were treated with doxorubicin hydrochloride, pancreas adenocarcinoma cell line PA-TU-8902 with gemcitabine hydrochloride, prostate carcinoma cell line DU145 with docetaxel and mitoxantrone hydrochloride and lung carcinoma cell line NCI-H460 was treated with docetaxel and cisplatin. Each dose of the respective chemotherapeutic drug was combined with Viscum album extract (VAE) in clinically relevant concentrations and proliferation and apoptosis were measured. RESULTS: VAE did not inhibit chemotherapy induced cytostasis and cytotoxicity in any of our experimental settings. At higher concentrations VAE showed an additive inhibitory effect. CONCLUSIONS: Our in vitro results suggest that no risk of safety by herb drug interactions has to be expected from the exposition of cancer cells to chemotherapeutic drugs and VAE simultaneously.

Reproducibility of effects of homeopathically potentised gibberellic acid on the growth of Lemna gibba L. in a randomised and blinded bioassay.

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.

Chronobiology of Viscum album L.: a time series of daily metabolomic fingerprints spanning 27 years.

Introduction: European mistletoe (Viscum album L.) has been gaining increasing interest in the field of oncology as a clinically relevant adjunctive treatment in many forms of cancer. In the field of phytopharmacology, harvesting time is pivotal. In the last century, a form of metabolomic fingerprinting based on pattern formation was proposed as a way to determine optimal harvesting times to ensure high quality of mistletoe as raw material for pharmaceutical use. In order to further evaluate the information obtained with this metabolomic fingerprinting method, we analysed a large time series of previously undigitised daily mistletoe chromatograms dating back to the 1950s. Methods: These chromatograms were scanned and evaluated using computerized image analysis, resulting in 12 descriptors for each individual chromatogram. We performed a statistical analysis of the data obtained, investigating statistical distributions, cross-correlations and time self-correlations. Results: The analysed dataset spanning about 27 years, contains 19,037 evaluable chromatograms in daily resolution. Based on the distribution and cross-correlation analyses, the 12 descriptors could be clustered into six independent groups describing different aspects of the chromatograms. One descriptor was found to mirror the annual rhythm being well correlated with temperature and a phase shift of 10 days. The time self-correlation analysis showed that most other descriptors had a characteristic self-correlation of ∼50 days, which points to further infradian rhythms (i.e., more than 24 h). Discussion: To our knowledge, this dataset is the largest of its type. The combination of this form of metabolomic fingerprinting with the proposed computer analysis seems to be a promising tool to characterise biological variations of mistletoe. Additional research is underway to further analyse the different rhythms present in this dataset.