scholarly journals Biological effects of menadione photochemistry: effects of menadione on biological systems may not involve classical oxidant production

2000 ◽  
Vol 350 (3) ◽  
pp. 797 ◽  
Author(s):  
Michael L. MCCORMICK ◽  
Gerene M. DENNING ◽  
Krzysztof J. RESZKA ◽  
Piotr BILSKI ◽  
Garry R. BUETTNER ◽  
...  
Homeopathy ◽  
2019 ◽  
Vol 109 (02) ◽  
pp. 079-086 ◽  
Author(s):  
Leoni Villano Bonamin ◽  
Renata Rossettini Palombro Pedro ◽  
Hannah Maureen G. Mota ◽  
Michelle S. Correia Aguiar ◽  
Sandra A. G. Pinto ◽  
...  

Abstract Background The mechanism by which highly diluted and agitated solutions have their effect is still unknown, but the development in recent years of new methods identifying changes in water and solute dipole moments is providing insights into potential modes of action. Objective The objective of the current study was to compare the biological effects of Antimonium crudum (AC) previously obtained by our group and already described in the literature with now measurable physico-chemical effects on solvatochromic dyes. Methods Different dilutions of AC and succussed water have been characterized with respect to their effect on the visible spectra of the solvatochromic dyes methylene violet (MV), a pyridinium phenolate (ET33), and a dimethylamino naphthalenone (BDN) compared with in-vitro action against Leishmania amazonensis-infected macrophages. Results Dye responses varied according to the dye used and the level of AC dilution and results were found to corroborate previously published in-vivo and in-vitro effects of AC. In addition, a very significant enhancement in the absorbance increase of MV was seen using the supernatant from AC 200cH-treated cells (15%; p < 0.0001) over that seen with AC 200cH itself (4%; p = 0.034), suggesting the amplification of ultra-high dilution effects by biological systems. Furthermore, supernatants from AC-treated cells increased the range of dilutions of AC that were capable of producing effects on the spectra of MV. The effect of AC dilutions on dye ET33 was eliminated by a weak electric current passed through potency solutions. Conclusion The data confirm a correspondence between the biological effects of dilutions of AC in-vitro and physico-chemical effects on solvatochromic dyes as measured by changes in their visible spectra. Results also indicate high dilutions of AC are sensitive to exposure to electric currents and biological systems.


Reproduction ◽  
2016 ◽  
Vol 152 (6) ◽  
pp. R263-R276 ◽  
Author(s):  
B J Houston ◽  
B Nixon ◽  
B V King ◽  
G N De Iuliis ◽  
R J Aitken

Mobile phone usage has become an integral part of our lives. However, the effects of the radiofrequency electromagnetic radiation (RF-EMR) emitted by these devices on biological systems and specifically the reproductive systems are currently under active debate. A fundamental hindrance to the current debate is that there is no clear mechanism of how such non-ionising radiation influences biological systems. Therefore, we explored the documented impacts of RF-EMR on the male reproductive system and considered any common observations that could provide insights on a potential mechanism. Among a total of 27 studies investigating the effects of RF-EMR on the male reproductive system, negative consequences of exposure were reported in 21. Within these 21 studies, 11 of the 15 that investigated sperm motility reported significant declines, 7 of 7 that measured the production of reactive oxygen species (ROS) documented elevated levels and 4 of 5 studies that probed for DNA damage highlighted increased damage due to RF-EMR exposure. Associated with this, RF-EMR treatment reduced the antioxidant levels in 6 of 6 studies that discussed this phenomenon, whereas consequences of RF-EMR were successfully ameliorated with the supplementation of antioxidants in all 3 studies that carried out these experiments. In light of this, we envisage a two-step mechanism whereby RF-EMR is able to induce mitochondrial dysfunction leading to elevated ROS production. A continued focus on research, which aims to shed light on the biological effects of RF-EMR will allow us to test and assess this proposed mechanism in a variety of cell types.


Author(s):  
Lise Bouchard ◽  
Mario Incayawar

Despite the importance and widespread presence of words in our life, the study of their effects on biological systems and the brain per se has been largely neglected. This chapter draws from biomedical and psychiatric research to illustrate the underlying biological effects of words used in a wide spectrum of human activity, such as writing, verbal communication, and reading, as well as the purposeful use of words during bullying and racist attacks, the triggering of placebo and nocebo effects, the words expressed during emotional and physical pain and psychopathology, and talkative psychotherapy. The authors conclude that words have a concrete impact on biological systems and the brain. This could be beneficial or deleterious. Therefore, positive doctor–patient communication is essential for achieving a high-quality medical encounter. It is suggested that medical linguistics could contribute to the development of clinical conversational strategies useful to physicians and psychotherapists treating patients suffering from pain and psychiatric disorders.


Author(s):  
Henry S. Slayter

Electron microscopic methods have been applied increasingly during the past fifteen years, to problems in structural molecular biology. Used in conjunction with physical chemical methods and/or Fourier methods of analysis, they constitute powerful tools for determining sizes, shapes and modes of aggregation of biopolymers with molecular weights greater than 50, 000. However, the application of the e.m. to the determination of very fine structure approaching the limit of instrumental resolving power in biological systems has not been productive, due to various difficulties such as the destructive effects of dehydration, damage to the specimen by the electron beam, and lack of adequate and specific contrast. One of the most satisfactory methods for contrasting individual macromolecules involves the deposition of heavy metal vapor upon the specimen. We have investigated this process, and present here what we believe to be the more important considerations for optimizing it. Results of the application of these methods to several biological systems including muscle proteins, fibrinogen, ribosomes and chromatin will be discussed.


Author(s):  
K. Shankar Narayan ◽  
Kailash C. Gupta ◽  
Tohru Okigaki

The biological effects of short-wave ultraviolet light has generally been described in terms of changes in cell growth or survival rates and production of chromosomal aberrations. Ultrastructural changes following exposure of cells to ultraviolet light, particularly at 265 nm, have not been reported.We have developed a means of irradiating populations of cells grown in vitro to a monochromatic ultraviolet laser beam at a wavelength of 265 nm based on the method of Johnson. The cell types studies were: i) WI-38, a human diploid fibroblast; ii) CMP, a human adenocarcinoma cell line; and iii) Don C-II, a Chinese hamster fibroblast cell strain. The cells were exposed either in situ or in suspension to the ultraviolet laser (UVL) beam. Irradiated cell populations were studied either "immediately" or following growth for 1-8 days after irradiation.Differential sensitivity, as measured by survival rates were observed in the three cell types studied. Pattern of ultrastructural changes were also different in the three cell types.


Author(s):  
Nicholas J Severs

In his pioneering demonstration of the potential of freeze-etching in biological systems, Russell Steere assessed the future promise and limitations of the technique with remarkable foresight. Item 2 in his list of inherent difficulties as they then stood stated “The chemical nature of the objects seen in the replica cannot be determined”. This defined a major goal for practitioners of freeze-fracture which, for more than a decade, seemed unattainable. It was not until the introduction of the label-fracture-etch technique in the early 1970s that the mould was broken, and not until the following decade that the full scope of modern freeze-fracture cytochemistry took shape. The culmination of these developments in the 1990s now equips the researcher with a set of effective techniques for routine application in cell and membrane biology.Freeze-fracture cytochemical techniques are all designed to provide information on the chemical nature of structural components revealed by freeze-fracture, but differ in how this is achieved, in precisely what type of information is obtained, and in which types of specimen can be studied.


2002 ◽  
Vol 69 ◽  
pp. 59-72 ◽  
Author(s):  
Kurt Drickamer ◽  
Andrew J. Fadden

Many biological effects of complex carbohydrates are mediated by lectins that contain discrete carbohydrate-recognition domains. At least seven structurally distinct families of carbohydrate-recognition domains are found in lectins that are involved in intracellular trafficking, cell adhesion, cell–cell signalling, glycoprotein turnover and innate immunity. Genome-wide analysis of potential carbohydrate-binding domains is now possible. Two classes of intracellular lectins involved in glycoprotein trafficking are present in yeast, model invertebrates and vertebrates, and two other classes are present in vertebrates only. At the cell surface, calcium-dependent (C-type) lectins and galectins are found in model invertebrates and vertebrates, but not in yeast; immunoglobulin superfamily (I-type) lectins are only found in vertebrates. The evolutionary appearance of different classes of sugar-binding protein modules parallels a development towards more complex oligosaccharides that provide increased opportunities for specific recognition phenomena. An overall picture of the lectins present in humans can now be proposed. Based on our knowledge of the structures of several of the C-type carbohydrate-recognition domains, it is possible to suggest ligand-binding activity that may be associated with novel C-type lectin-like domains identified in a systematic screen of the human genome. Further analysis of the sequences of proteins containing these domains can be used as a basis for proposing potential biological functions.


2019 ◽  
Vol 3 (5) ◽  
pp. 435-443 ◽  
Author(s):  
Addy Pross

Despite the considerable advances in molecular biology over the past several decades, the nature of the physical–chemical process by which inanimate matter become transformed into simplest life remains elusive. In this review, we describe recent advances in a relatively new area of chemistry, systems chemistry, which attempts to uncover the physical–chemical principles underlying that remarkable transformation. A significant development has been the discovery that within the space of chemical potentiality there exists a largely unexplored kinetic domain which could be termed dynamic kinetic chemistry. Our analysis suggests that all biological systems and associated sub-systems belong to this distinct domain, thereby facilitating the placement of biological systems within a coherent physical/chemical framework. That discovery offers new insights into the origin of life process, as well as opening the door toward the preparation of active materials able to self-heal, adapt to environmental changes, even communicate, mimicking what transpires routinely in the biological world. The road to simplest proto-life appears to be opening up.


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