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Dive into the research topics where Eduard van Wijk is active.

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Featured researches published by Eduard van Wijk.


PLOS ONE | 2014

Ultraweak photon emission as a non-invasive health assessment: A systematic review

John A. Ives; Eduard van Wijk; Namuun Bat; Cindy Crawford; Avi Walter; Wayne B. Jonas; Roeland van Wijk; Jan van der Greef

We conducted a systematic review (SR) of the peer reviewed scientific literature on ultraweak photon emissions (UPE) from humans. The question was: Can ultraweak photon emissions from humans be used as a non-invasive health assessment? A systematic search was conducted across eight relevant databases: PubMed/MEDLINE, BIOSIS, CINAHL, PSYCHINFO, All of Cochrane EBM databases, GIDEON, DoD Biomedical Research, and clinicaltrials.gov from database inception to October 2011. Of the 1315 studies captured by the search strategy, 56 met the inclusion criteria, out of which 1 was a RCT, 27 were CCT, and 28 were observational and descriptive studies. There were no systematic reviews/meta-analyses that fit the inclusion criteria. In this report, the authors provide an assessment of the quality of the RCT included; describe the characteristics of all the included studies, the outcomes assessed, and the effectiveness of photon emission as a potential health assessment tool. This report demonstrates that the peer reviewed literature on UPE and human UPE measurement in particular is surprisingly large. Most of the human UPE literature is of good to high quality based on our systematic evaluation. However, an evaluation tool for systematically evaluating this type of “bio-evaluation” methodology is not currently available and would be worth developing. Publications in the peer reviewed literature over the last 50 years demonstrate that the use of “off-the-shelf” technologies and well described methodologies for the detection of human photon emissions are being used on a regular basis in medical and research settings. The overall quality of this literature is good and the use of this approach for determining inflammatory and oxidative states of patients indicate the growing use and value of this approach as both a medical and research tool.


Journal of Photochemistry and Photobiology B-biology | 2010

Using ultra-weak photon emission to determine the effect of oligomeric proanthocyanidins on oxidative stress of human skin

Eduard van Wijk; Roelan D. Van Wijk; Saskia Bosman

Exposure of skin to ultraviolet (UV) radiation triggers oxidative stress in skin tissue that can lead to erythema, early skin aging or even cancer. It is suggested that oligomeric proanthocyanidins (OPCs), phytonutrients that belong to the polyphenol family have an anti-oxidant/anti-inflammatory activity on the skin. Measuring ultra-weak photon emission (UPE) is a non-invasive, fairly-sensitive and convenient technique for continuously monitoring oxidative stress. The present study was undertaken to confirm anti-oxidant activity of the specific OPCs cream formulation in human skin by measuring UPE of skin. In the present study 25 healthy female subjects participated. As a baseline measurement of skin, UPE was recorded from the dorsal surface of the subjects hands before (spontaneous UPE) and after exposure to UV (UV-induced UPE). The effects of the OPCs cream on spontaneous and UV-induced UPE were measured using a fractionated UV exposure protocol. UV exposure resulted in an increase in UPE from both hands. Repeat UV exposure also resulted in a long-term increase of spontaneous UPE. This is likely due to depletion of anti-oxidant capacity of skin resulting in sensitization of skin to UV. It was assessed by measuring spontaneous UPE at 80 min after each UV exposure. Application of the OPCs cream immediately after UV exposure resulted in a significant (approx. 30%) decrease in UV-induced UPE. Topical OPCs cream application also reduced sensitization of skin to UV following repeated UV exposure (i.e., reduced long-term increase in spontaneous UPE). This study indicates that the specific OPCs cream formulation significantly decreases UV-induced oxidative stress in human skin based on UPE measurement. It therefore suggests that regular use of this OPCs cream might protect skin from harmful effects of UV.


PLOS ONE | 2013

Imaging of ultra-weak photon emission in a rheumatoid arthritis mouse model

Eduard van Wijk; Masaki Kobayashi; Roeland van Wijk; Jan van der Greef

Ultra-weak photon emission (UPE) of a living system received scientific attention because of its potential for monitoring increased levels of reactive oxygen species (ROS) in the pathogenesis of rheumatoid arthritis (RA). In this study, a highly sensitive cryogenic charge-coupled device (CCD) camera was used to monitor in a RA mouse model the photon emission both without and with luminol. For that purpose, arthritis was induced in mice utilizing a repeated co-administration of type II collagen with lipopolysaccharide. Quantitative imaging of ultra-weak photon emission of the front and back paws of the animals was initiated 70 days after the first injection. All of the animals were measured once without luminol and once again immediately after luminol injection. Data illustrated a higher UPE intensity after initiating arthritis by CII-injection of the animals. The increase in UPE intensity was measured with and without using luminol indicating that this imaging technology may be useful for the future study of human RA.


Journal of Photochemistry and Photobiology B-biology | 2013

Attributes characterizing spontaneous ultra-weak photon signals of human subjects.

Rajendra P. Bajpai; Eduard van Wijk; Roeland van Wijk; Jan van der Greef

Sixty visible range photon signals spontaneously emitted from the dorsal side of both hands of fifteen human subjects are analyzed with the aim of finding their attributes. The signals are of 30 min duration and detected in bins of 50 ms by two synchronized photo multipliers sensitive in the range (290-630 nm). Each signal is a time series of 36,000 elements. The attributes of its signal are determined from the statistical properties of time series. The mean and variance of time series determine the attributes signal strength and intercept (p₀) and slope (p₁) of the Fano Factor curve. The photon count distribution of the time series determines squeezed state parameters |α|, r, θ and ϕ, squeezed state index (SSI), and sum of the squares of residue (SSR). The correlation between simultaneously detected signals determines intercept (c₀) and slope (c₁) of their correlation curve. The variability of attributes is studied by calculating them in smaller intervals covering the entire signal. The profile of attribute at 12 sites in a subject is more informative and biologically relevant.


Journal of Photochemistry and Photobiology B-biology | 2010

Statistical analysis of the spontaneously emitted photon signals from palm and dorsal sides of both hands in human subjects

Eduard van Wijk; Roeland Van Wijk; Rajendra P. Bajpai; Jan van der Greef

Photon signals emitted spontaneously from dorsal and palm sides of both hands were recorded using 6000 time windows of size T=50 ms in 50 healthy human subjects. These photon signals demonstrated universal behaviour by variance and mean. The data sets for larger time windows up to T=50s were obtained by merging the data recorded with T=50 ms. The behaviour of Fano factor regarding different window sizes was investigated. The Fano factor hovered around one in signals up to T=3s and increased slowly with the increase in window size. This indicated super-Poissonian distribution of photo counts. The Fano factor curve F(T) obtained by averaging all subjects and locations had a characteristic shape. Data suggest that the shape is essentially a combination of a smaller sub-population of individuals with sub-Poissonian and a larger sub-population with predominantly super-Poissonian photo count distribution. Averaging the data obtained by randomly shuffling observed data sets was flat and did not show any structure with T. The same applied both to the observed background data sets and the data sets obtained by randomly shuffling background in 50 measurements. The Fano factor was also flat in 50 measurements documented both by a standard LED as well as its shuffled data sets. The structure in the shape F(T) is characteristic of human signals. It may contain valuable information about metabolic processes and may have diagnostic relevance.


Journal of Acupuncture and Meridian Studies | 2010

Human Ultraweak Photon Emission and the Yin Yang Concept of Chinese Medicine

Roeland van Wijk; Jan van der Greef; Eduard van Wijk

Abstract The relationship between connective tissue and meridian function is discussed in terms of energy transmission. The network of hydrogen-bonded water molecules interspersed within the collagen fibrillar matrix is especially significant for both the sensitivity of connective tissue to weak signals of mechanical pressure, heat, or electricity and the electrical intercommunication that may correlate with the meridian acupuncture system. Special electromagnetic properties of connective tissue have similar collective properties of ultraweak photon emission. A relationship between ultraweak photon emission and yin yang dynamics is based on three types of ultraweak photon emission studies, focusing on diurnal and annual dynamics, diseased states, and acupuncture points. A novel concept explains the functional (health) integrity of physiologic systems in relation to the left-right balance in ultraweak photon emission by pointing to, (1) balanced corticoneuromusculoskeletal activities and triboluminescent aspects of ultraweak photon emission by skeletal structures, and (2) local fine-tuning in oxygen supply and the formation of radical oxygen species. This approach offers testable hypotheses for further validation utilizing a combination of human photon recording techniques and specialized metabolomics for the estimation of organ-specific oxidative states.


Journal of Photochemistry and Photobiology B-biology | 2016

Effects of growth altitude on chemical constituents and delayed luminescence properties in medicinal rhubarb

Mengmeng Sun; Li Li; Mei Wang; Eduard van Wijk; Min He; Roeland van Wijk; Slavik Koval; Thomas Hankemeier; Jan van der Greef; Shengli Wei

To improve the quality control of herbal drugs, there has been a major shift from evaluating individual chemicals to evaluating multiple-constituent chemicals, given the multi-pharmacology nature of herbal drugs. Therefore, rapid, systematic assays are needed in order to assess the quality of medicinal herbs using a comprehensive, integrated approach. Light-induced delayed luminescence (DL) is used to measure decaying long-term ultra-weak photon emissions following excitation with light. DL is considered to be a sensitive indicator for characterizing the properties of biological systems and herbal medicines with various therapeutic properties. The aim of this study was to examine the feasibility of using DL as a novel quality-assessment tool using rhubarb material as a model system, and to establish the correlation between DL parameters and the chemical constituents of rhubarb. Raw roots and rhizomes were collected from rhubarb (Rheum palmatum L.) at various elevations in western China. HPLC analysis was used to identify fourteen bioactive constituents. Five DL parameters were calculated from the DL decay curves of the rhubarb samples. Statistical tools, including principal component analysis, were used to classify the rhubarb samples using data obtained using two different assays. Finally, Spearmans correlation coefficient was calculated to quantify the correlation between the bioactive compounds and corresponding DL parameters. We found that both the chemical analysis and DL measurements reflect variations in the quality of rhubarb due to environment factor. The DL parameters were correlated significantly with the bioactive chemical constituents. Our results indicate that DL is a promising tool for evaluating multiple constituents and for assessing the therapeutic properties of herbal medicines. Thus, DL may be used as part of a comprehensive system for assessing the quality and/or therapeutic properties of herbal medicines.


Journal of Physics: Conference Series | 2011

Photon Counts Statistics in Leukocyte Cell Dynamics

Eduard van Wijk; Jan van der Greef; Roeland van Wijk

In the present experiment ultra-weak photon emission/ chemiluminescence from isolated neutrophils was recorded. It is associated with the production of reactive oxygen species (ROS) in the respiratory burst process which can be activated by PMA (Phorbol 12-Myristate 13-Acetate). Commonly, the reaction is demonstrated utilizing the enhancer luminol. However, with the use of highly sensitive photomultiplier equipment it is also recorded without enhancer. In that case, it can be hypothesized that photon count statistics may assist in understanding the underlying metabolic activity and cooperation of these cells. To study this hypothesis leukocytes were stimulated with PMA and increased photon signals were recorded in the quasi stable period utilizing Fano factor analysis at different window sizes. The Fano factor is defined by the variance over the mean of the number of photon within the observation time. The analysis demonstrated that the Fano factor of true signal and not of the surrogate signals obtained by random shuffling increases when the window size increased. It is concluded that photon count statistics, in particular Fano factor analysis, provides information regarding leukocyte interactions. It opens the perspective to utilize this analytical procedure in (in vivo) inflammation research. However, this needs further validation.


Scientific Reports | 2017

Ultra-weak photon emission as a dynamic tool for monitoring oxidative stress metabolism

Rosilene Cristina Rossetto Burgos; Johannes C. Schoeman; Lennart Jan van Winden; Kateřina Červinková; Rawi Ramautar; Eduard van Wijk; Michal Cifra; Ruud Berger; Thomas Hankemeier; Jan van der Greef

In recent years, excessive oxidative metabolism has been reported as a critical determinant of pathogenicity in many diseases. The advent of a simple tool that can provide a physiological readout of oxidative stress would be a major step towards monitoring this dynamic process in biological systems, while also improving our understanding of this process. Ultra-weak photon emission (UPE) has been proposed as a potential tool for measuring oxidative processes due to the association between UPE and reactive oxygen species. Here, we used HL-60 cells as an in vitro model to test the potential of using UPE as readout for dynamically monitoring oxidative stress after inducing respiratory burst. In addition, to probe for possible changes in oxidative metabolism, we performed targeted metabolomics on cell extracts and culture medium. Lastly, we tested the effects of treating cells with the NADPH oxidase inhibitor diphenyleneiodonium chloride (DPI). Our results show that UPE can be used as readout for measuring oxidative stress metabolism and related processes.


Journal of Photochemistry and Photobiology B-biology | 2016

Tracking biochemical changes correlated with ultra-weak photon emission using metabolomics

Rosilene Cristina Rossetto Burgos; Kateřina Červinková; Tom van der Laan; Rawi Ramautar; Eduard van Wijk; Michal Cifra; Slavik Koval; Ruud Berger; Thomas Hankemeier; Jan van der Greef

Ultra-weak photon emission (UPE) is light emitted spontaneously by biological systems without the use of specific luminescent complexes. UPE is emitted in the near-UV/UV-Vis/near-IR spectra during oxidative metabolic reactions; however, the specific pathways involved in UPE remain poorly understood. Here, we used HL-60 cells, a human promyelocytic cell line that is often used to study respiratory burst, as a model system to measure UPE kinetics together with metabolic changes. HL-60 cells were differentiated into neutrophil-like cells by culturing in all-trans-retinoic acid for 7days. We then used a targeted metabolomics approach with capillary electrophoresis-mass spectrometry to profile intracellular metabolites in HL-60 cells and to investigate the biochemical changes based on the measured UPE profile. Our analysis revealed that the levels of specific metabolites, including putrescine, creatine, β-alanine, methionine, hydroxyproline, serine, and S-adenosylmethionine, were significantly altered in HL-60 cells after inducing respiratory burst. A comparison with recorded UPE data revealed that the changes in putrescine, glutathione, sarcosine, creatine, β-alanine, methionine, and hydroxyproline levels were inversely correlated with the change in UPE intensity. These results suggest that these metabolic pathways, particular the methionine pathway, may play a role in the observed changes in UPE in HL-60 cells and therefore demonstrate the potential for using UPE to monitor metabolic changes.

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Michal Cifra

Academy of Sciences of the Czech Republic

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