scholarly journals Use of plant bioassays in homeopathic basic research - a systematic review

2021 ◽  
Vol 11 (40) ◽  
pp. 140-141
Author(s):  
Stephan Baumgartner ◽  
Lucietta Betti ◽  
Peter Heusser ◽  
Tim Jäger ◽  
Claudia Scherr ◽  
...  
Keyword(s):  
False Negative ◽  
Experimental Studies ◽  
Basic Research ◽  
Negative Control ◽  
Systematic Research ◽  
Sufficient Information ◽  
Negative Results ◽  
Specific Effects ◽  
Proper Interpretation ◽  
Plant Bioassays

Background: Experimental research on the effects of treatments with homeopathic preparations on plants was last reviewed in 1990. Aims: The objective was to compile a systematic literature review on plant bioassays in homeopathic basic research using predefined criteria. Methods: Literature search was carried out on publications that reported experiments with homeopathic preparations on whole plants, seeds, plant parts or cells from 1920 to 2010, in healthy, abiotically or biotically stressed conditions. Outcomes had to be measured by established state-of-the-art procedures and statistically evaluated. Using a Manuscript Information Score (MIS) those publications were identified that provided sufficient information for proper interpretation (MIS > 5). Further evaluation focused on the use of adequate controls to investigate specific effects of homeopathic preparations and on the use of systematic negative control experiments to ensure proper system performance. Results: A total of 157 publications with plants were identified [1–3]. The 157 publications described a total of 167 experimental studies. 84 studies included statistics and 48 had a MIS > 5 allowing proper interpretation. 29 studies were identified with adequate controls to identify specific effects of homeopathic preparations, reporting significant effects of decimal and centesimal homeopathic potencies, including dilution levels beyond Avogadro’s number. Studies that tested series of consecutive potency levels reported a non-linear and discontinuous relation between effect and potency level. There were many individual studies with diverse methods and very few replication trials. 10 studies reported use of systematic negative control experiments, yielding evidence for the stability of the experimental set-up. Conclusions: Plant models appear to be a useful approach to investigate basic research questions on homeopathic preparations, but more independent replication trials and systematic research are needed. Systematic negative control experiments should be implemented on a routine basis to exclude false-positive and false-negative results.

Defining an Adequate Dose of Acupuncture Using a Neurophysiological Approach – a Narrative Review of the Literature

2008 ◽  
Vol 26 (2) ◽  
pp. 111-120 ◽  
Author(s):  
Adrian White ◽  
Mike Cummings ◽  
Panos Barlas ◽  
Francesco Cardini ◽  
Jacqueline Filshie ◽  
...  
Keyword(s):  
Systematic Reviews ◽  
Acupuncture Treatment ◽  
Experimental Studies ◽  
Basic Research ◽  
Strong Argument ◽  
Treatment Protocols ◽  
Negative Results ◽  
Adequate Dose ◽  
Definition Of ◽  
Patient’S Perception

Many different styles of acupuncture practice exist, and lack of agreement on the optimal acupuncture treatment for any particular condition may mean that some patients do not receive the best treatment. This uncertainty also makes the negative results of sham controlled trials difficult to interpret. Unless we can be sure that both adequate acupuncture and an inactive sham were used in a particular trial, then that trial should not be interpreted as dismissing acupuncture for that condition. Acupuncture practice clearly involves much more than needling procedures, but there is a strong argument for elucidating the role of those needling procedure first. The components of acupuncture needling procedures have been described in the STRICTA document, but it is also clear that the patient's perception of needling is relevant for the outcome of treatment. We therefore recommend the concept of ‘dose’ of acupuncture needling, which should include both the stimulus given to the patient, and certain aspects of the patient's perceptions and response that are known to be linked to the subsequent therapeutic response. We propose the following definition of dose: the physical procedures applied in each session, using one or more needles, taking account of the patient's resulting perception (sensory, affective and cognitive) and other responses (including motor). The dose may be affected by the state of the patient (eg nervous, immune and endocrine systems); different doses may be required for different conditions. The constituents of an adequate dose can be established initially by clinical opinion and subsequently by empirical evidence from experimental studies, which may be either clinical or basic research studies. Systematic reviews which do not consider the adequacy of the acupuncture treatment may have unreliable conclusions. Out of 47 recent systematic reviews, only six have applied some criteria for adequacy. Five used a rating system or conducted a subgroup analysis, and one excluded studies from the analysis altogether if they did not meet criteria for adequacy. Research into what constitutes an adequate dose of acupuncture has long been neglected and is now urgent. Clinical studies that compare the effects of different treatment protocols are probably the most reliable source of evidence, and may also demonstrate a dose-response relationship.

scholarly journals Intact proviral DNA assay analysis of large cohorts of people with HIV provides a benchmark for the frequency and composition of persistent proviral DNA

2020 ◽  
Vol 117 (31) ◽  
pp. 18692-18700 ◽  
Author(s):  
Francesco R. Simonetti ◽  
Jennifer A. White ◽  
Camille Tumiotto ◽  
Kristen D. Ritter ◽  
Mian Cai ◽  
...  
Keyword(s):  
T Cells ◽  
False Negative ◽  
Basic Research ◽  
The United States ◽  
Quantitative Evidence ◽  
Dna Assay ◽  
Proviral Dna ◽  
Negative Results ◽  
Hiv 1

A scalable approach for quantifying intact HIV-1 proviruses is critical for basic research and clinical trials directed at HIV-1 cure. The intact proviral DNA assay (IPDA) is a novel approach to characterizing the HIV-1 reservoir, focusing on the genetic integrity of individual proviruses independent of transcriptional status. It uses multiplex digital droplet PCR to distinguish and separately quantify intact proviruses, defined by a lack of overt fatal defects such as large deletions and APOBEC3G-mediated hypermutation, from the majority of proviruses that have such defects. This distinction is important because only intact proviruses cause viral rebound on ART interruption. To evaluate IPDA performance and provide benchmark data to support its implementation, we analyzed peripheral blood samples from 400 HIV-1+adults on ART from several diverse cohorts, representing a robust sample of treated HIV-1 infection in the United States. We provide direct quantitative evidence that defective proviruses greatly outnumber intact proviruses (by >12.5 fold). However, intact proviruses are present at substantially higher frequencies (median, 54/106CD4+T cells) than proviruses detected by the quantitative viral outgrowth assay, which requires induction and in vitro growth (∼1/106CD4+T cells). IPDA amplicon signal issues resulting from sequence polymorphisms were observed in only 6.3% of individuals and were readily apparent and easily distinguished from low proviral frequency, an advantage of the IPDA over standard PCR assays which generate false-negative results in such situations. The large IPDA dataset provided here gives the clearest quantitative picture to date of HIV-1 proviral persistence on ART.

scholarly journals SARS-CoV-2 Detection for Diagnosis Purposes in the Setting of a Molecular Biology Research Lab

2020 ◽  
Vol 3 (3) ◽  
pp. 59 ◽  
Author(s):  
Damien Coupeau ◽  
Nicolas Burton ◽  
Noémie Lejeune ◽  
Suzanne Loret ◽  
Astrid Petit ◽  
...  
Keyword(s):  
Molecular Biology ◽  
False Negative ◽  
Basic Research ◽  
Clinical Samples ◽  
Acid Extraction ◽  
Public Health Systems ◽  
Negative Results ◽  
False Negative Results ◽  
Biology Lab ◽  
Biology Research

The emergence of the SARS-CoV-2 virus and the exponential growth of COVID-19 cases have created a major crisis for public health systems. The critical identification of contagious asymptomatic carriers requires the isolation of viral nucleic acids, reverse transcription, and amplification by PCR. However, the shortage of specific proprietary reagents or the lack of automated platforms have seriously hampered diagnostic throughput in many countries. Here, we provide a procedure for SARS-CoV-2 detection for diagnostic purposes from clinical samples in the setting of a basic research molecular biology lab. The procedure details the necessary steps for daily analysis of up to 500 clinical samples with a team composed of 12 experienced researchers. The protocol has been designed to rely on widely available reagents and devices, to cope with heterogeneous clinical specimens, to guarantee nucleic acid extraction from very scarce biological material, and to minimize the rate of false-negative results.

scholarly journals Amylenes Do Not Lead to Bacterial Mutagenicity in Contrast to Structurally Related Epoxides

2014 ◽  
Vol 2014 ◽  
pp. 1-5
Author(s):  
Götz A. Westphal ◽  
Carolin Tüshaus ◽  
Christian Monsé ◽  
Nina Rosenkranz ◽  
Thomas Brüning ◽  
...  
Keyword(s):  
Parent Strain ◽  
Ames Test ◽  
False Negative ◽  
Positive Control ◽  
Negative Control ◽  
Unsaturated Hydrocarbons ◽  
Negative Results ◽  
False Negative Results ◽  
Mutagenic Effects ◽  
Gas Tight

Amylenes are unsaturated hydrocarbons (C5H10), such as 1-pentene, 2-pentene, 2-methyl-but-1-en (3-methyl-1-butene), 2-methyl-but-2-en (isopentene), and 3-methyl-but-1-en. We investigated bacterial mutagenicity of 1-pentene, 2-pentene, and 3-methyl-but-1-en in the Ames test. 2-Pentene was investigated as racemate and as pure diastereomers. We included the methyltransferase deficientSalmonellaTyphimurium strain YG7108 and the application of a gas-tight preincubation to reduce the risk of false negative results. 1,2-Epoxypentane which may arise from 1-pentene was used as positive control. None of the investigated amylenes showed mutagenic effects, whereas 1,2-epoxypentane was mutagenic exceeding 100 μg per plate. An exceptional high reverse mutation in the negative control plates in the experiments with 1,2-epoxypentane was obviously caused by evaporation into the incubator which was shown by placing the control plates in a separate apparatus. No differences were seen upon use of YG7108 and its parent strain TA1535. In conclusion, 1,2-epoxypentane is most probably not a substrate of the deleted bacterial methyltransferases. The comparison of the bacterial mutagenicity of the investigated amylenes and 1,2-epoxipentane suggests that epoxidation of amylenes in the S9-mix does not proceed effectively or is counterbalanced by detoxifying reactions. The assessment of mutagenic effects of short chained aliphatic epoxides can be underestimated due to the evaporation of these compounds.

scholarly journals Methodological limitations in experimental studies on symptom development in individuals with idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) – a systematic review

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Kristina Schmiedchen ◽  
Sarah Driessen ◽  
Gunnhild Oftedal
Keyword(s):  
Systematic Review ◽  
Electromagnetic Fields ◽  
Statistical Power ◽  
False Negative ◽  
Experimental Studies ◽  
Symptom Development ◽  
Nocebo Effect ◽  
Idiopathic Environmental Intolerance ◽  
Negative Results ◽  
Environmental Intolerance

Abstract Background Hypersensitivity to electromagnetic fields (EMF) is a controversial condition. While individuals with idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) claim to experience health complaints upon EMF exposure, many experimental studies have found no convincing evidence for a physical relation. The aim of this systematic review was to evaluate methodological limitations in experimental studies on symptom development in IEI-EMF individuals that might have fostered false positive or false negative results. Furthermore, we compared the profiles of these limitations between studies with positive and negative results. Methods The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guided the methodological conduct and reporting. Eligible were blinded experimental studies that exposed individuals with IEI-EMF to different EMF exposure levels and queried the development of symptoms during or after each exposure trial. Strengths and limitations in design, conduct and analysis of individual studies were assessed using a customized rating tool. Results Twenty-eight studies met the eligibility criteria and were included in this review. In many studies, both with positive and negative results, we identified methodological limitations that might have either fostered false or masked real effects of exposure. The most common limitations were related to the selection of study participants, the counterbalancing of the exposure sequence and the effectiveness of blinding. Many studies further lacked statistical power estimates. Methodically sound studies indicated that an effect of exposure is unlikely. Conclusion Overall, the evidence points towards no effect of exposure. If physical effects exist, previous findings suggest that they must be very weak or affect only few individuals with IEI-EMF. Given the evidence that the nocebo effect or medical/mental disorders may explain the symptoms in many individuals with IEI-EMF, additional research is required to identify the various factors that may be important for developing IEI-EMF and for provoking the symptoms. We recommend the identification of subgroups and exploring IEI-EMF in the context of other idiopathic environmental intolerances. If further experimental studies are conducted, they should preferably be performed at the individual level. In particular, to increase the likelihood of detecting hypersensitive individuals, if they exist, we encourage researchers to achieve a high credibility of the results by minimizing sources of risk of bias and imprecision.

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

Homeopathy ◽  
2018 ◽  
Vol 107 (02) ◽  
pp. 115-129 ◽  
Author(s):  
Stephan Baumgartner ◽  
Anezka Sokol ◽  
Roman Huber ◽  
Paul Doesburg ◽  
Tim Jäger ◽  
...  
Keyword(s):  
Influencing Factors ◽  
Basic Research ◽  
Test System ◽  
Negative Control ◽  
Research Field ◽  
Original Study ◽  
System Stability ◽  
Test Systems ◽  
Specific Effects ◽  
Publication Quality

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.

Critical Evaluation of Impedance Phlebography for the Diagnosis of Deep Vein Thrombosis

1974 ◽  
Vol 31 (02) ◽  
pp. 273-278
Author(s):  
Kenneth K Wu ◽  
John C Hoak ◽  
Robert W Barnes ◽  
Stuart L Frankel
Keyword(s):  
Deep Vein Thrombosis ◽  
False Positive ◽  
False Negative ◽  
Critical Evaluation ◽  
Original Method ◽  
Vein Thrombosis ◽  
Negative Results ◽  
False Negative Results ◽  
Deep Vein ◽  
Positive Results

SummaryIn order to evaluate its daily variability and reliability, impedance phlebography was performed daily or on alternate days on 61 patients with deep vein thrombosis, of whom 47 also had 125I-fibrinogen uptake tests and 22 had radiographic venography. The results showed that impedance phlebography was highly variable and poorly reliable. False positive results were noted in 8 limbs (18%) and false negative results in 3 limbs (7%). Despite its being simple, rapid and noninvasive, its clinical usefulness is doubtful when performed according to the original method.

The role of serum periostin in the diagnosis of asthma: A meta-analysis

2020 ◽  
Vol 41 (4) ◽  
pp. 240-247
Author(s):  
Lei Yang ◽  
Qingtao Zhao ◽  
Shuyu Wang
Keyword(s):  
Diagnostic Accuracy ◽  
Meta Analysis ◽  
Characteristic Curve ◽  
False Negative ◽  
Summary Receiver Operating Characteristic ◽  
True Negative ◽  
Negative Results ◽  
Noninvasive Biomarker ◽  
Sensitivity Specificity ◽  
Serum Periostin

Background: Serum periostin has been proposed as a noninvasive biomarker for asthma diagnosis and management. However, its accuracy for the diagnosis of asthma in different populations is not completely clear. Methods: This meta-analysis aimed to evaluate the diagnostic accuracy of periostin level in the clinical determination of asthma. Several medical literature data bases were searched for relevant studies through December 1, 2019. The numbers of patients with true-positive, false-positive, false-negative, and true-negative results for the periostin level were extracted from each individual study. We assessed the risk of bias by using Quality Assessment of Diagnostic Accuracy Studies 2. We used the meta-analysis to produce summary estimates of accuracy. Results: In total, nine studies with 1757 subjects met the inclusion criteria. The pooled estimates of sensitivity, specificity, and diagnostic odds ratios for the detection of asthma were 0.58 (95% confidence interval [CI], 0.38‐0.76), 0.86 (95% CI, 0.74‐0.93), and 8.28 (95% CI, 3.67‐18.68), respectively. The area under the summary receiver operating characteristic curve was 0.82 (95% CI, 0.79‐0.85). And significant publication bias was found in this meta‐analysis (p = 0.39). Conclusion: Serum periostin may be used for the diagnosis of asthma, with moderate diagnostic accuracy.

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