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Thermomagnetic Activation of Cellular Ion Channels to Control Cellular Activity
Published in Jon Dobson, Carlos Rinaldi, Nanomagnetic Actuation in Biomedicine, 2018
Cells, the basic building blocks of life, are spatially structured, yet highly dynamic factories that produce almost everything an organism needs. Their functions require that they communicate with each other on many levels and timescales, from millisecond electronic communication in the heart to synchronize contraction, to communication lasting minutes, hours, and even days, and over long distances across the body via chemical messengers, such as hormones. Many human diseases are caused by erroneous signal procession: diabetes is either caused by the inability to produce the signaling hormone insulin or by the desensitization of its receptor; the majority of cancers result from erroneous processing of growth signaling delivered by growth hormones. Hence, the development of tools to communicate with cells inside the intact organism is of great interest for basic research and new therapeutic approaches. Ideally, we find ways to read the state of single cell and then relate back a message to a cell without having to disrupt the organism.
Treatment Options for Chemical Sensitivity
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 5, 2017
William J. Rea, Kalpana D. Patel
For didactic reasons, we will distinguish below receptor “desensitization” and “tachyphylaxis” from “impairment of neuronal functions.” Both desensitization and tachyphylaxis occur at the receptor level. By desensitization, we mean a rapid loss of activity of the receptor occupied by an agonist. For example, in the continuous presence of capsaicin, histamine- or serotonin-elicited currents quickly fade. However, the neutralization dose of capsaicin or the other two can be used to quell some cases of chemical sensitivity. We use these three as rescue antigens to immediately turn off a nonspecific reaction.
Aerobiology of Pollen and Pollen Antigens
Published in Christopher S. Cox, Christopher M. Wathes, Bioaerosols Handbook, 2020
Immunotherapy (desensitization, hyposensitization) consists of aseries of subcutaneous injections of allergen extract. This may be expected to reduce the patient’s reactivity to the allergen in question. In the first phase, increasing dosages of the allergen are given at regular intervals. In the second phase, the highest tolerated dose is given as a maintenance dose. Hyposensitization only is effective if the patient is treated with extracts representing the actual sensitization source.56
Toxicity and effects on anuran tadpole metamorphosis of the anthranilic diamide insecticides chlorantraniliprole and cyantraniliprole
Published in Journal of Toxicology and Environmental Health, Part A, 2023
Shirley Vivian Daniela Fonseca Peña, Julie Céline Brodeur
Non-monotonic dose-responses (NMDR) such as the one detected here with respect to the influence of CHLO on amphibian metamorphosis are frequently associated with endocrine disrupting chemicals (EDCs) (Hill, Myers, and Vandenberg 2018). NMDR may arise from numerous molecular mechanisms such as (1) opposing effects induced by multiple receptors differing in their affinity, (2) receptor desensitization, (3) negative feedback with increasing dose, or (4) dose-dependent metabolism modulation (Lagarde et al. 2015). Greenwood, Belz, and Weiser (2022) recently demonstrated a conserved mechanism of NMDR at the molecular level, in which the ability of a multimeric protein to simultaneously bind a substrate and its competitor on different subunits made the protein potentially susceptible to NMDR. Incidentally, although structural information on the thyroid hormone receptor remains limited, it is known to form di- and tri- multimers (Kleinau et al. 2017).
Potency matters: Impacts of embryonic exposure to nAChR agonists thiamethoxam and nicotine on hatching success, growth, and neurobehavior in larval zebrafish
Published in Journal of Toxicology and Environmental Health, Part A, 2022
Shayla Victoria, Megan Hein, Elisabeth Harrahy, Tisha C King-Heiden
The predator escape response is a reflexive and innate behavior that occurs through the detection of water flow at the lateral line and allows larvae to escape predators (McGee et al. 2009; McHenry et al. 2009). As expected, chronic exposure to low concentrations of NIC produced alterations in the predatory escape response in surviving larvae. Impacts following chronic exposure to TM were nonmonotonic and subtle. The nonmonotonic dose responses might be associated with desensitization of the nAChRs; however, Liu et al. (2018) reported that chronic exposure to higher concentrations (approximately 100 µg TM/L) altered locomotor activity in zebrafish larvae. Again, fathead minnow larvae appeared to be more sensitive to TM compared to zebrafish with respect to effects on the predatory escape response (Victoria et al. 2022). It should be noted that Victoria et al. (2022) used a vibrational stimulus, while a tactile stimulus was employed in this study to initiate the escape response. Taken together, current evidence supports the potential for TM to interfere with complex behaviors in fish, as previously demonstrated for imidacloprid (Crosby et al. 2015; Lee-Jenkins and Robinson 2018). Since predators are one of the largest threats to larval fish in the wild, longer latency periods and slower escape velocities might impact the ability of fish larvae to escape natural predators, thereby impairing recruitment success (Nair, Nguyen, and McHenry 2017; Painter et al. 2009). Given the pseudo-persistence of neonicotinoids within aquatic environments due to frequent input, this warrants further evaluation.
Windows of sensitivity to toxic chemicals in the development of reproductive effects: an analysis of ATSDR’s toxicological profile database
Published in International Journal of Environmental Health Research, 2018
Melanie C Buser, Henry G Abadin, John L Irwin, Hana R Pohl
Principal rules of toxicology discussed in our previous papers include: (1) the dose of the chemical, (2) time of exposure (sensitive window), and (3) species differences (Buser and Pohl 2015; Ingber and Pohl 2016). These variables are also critical for determining effects that tested chemicals may have on the development of the reproductive system. In regard to dose, it should be noted that chemicals that exhibit non-monotonic dose response curves (e.g. bisphenol A) could theoretically produce different windows of sensitivity in response to high and very low doses. These responses can result from several molecular mechanisms such as opposing effects induced by multiple receptors differing by their affinity, receptor desensitization, negative feedback with increasing dose, or dose-dependent metabolism modulation (Lagarde et al. 2015). However, such responses were not detected in this review. The understanding of non-monotonic dose responses stems from observing changing direction of effect over the range of doses examined within a study (Vandenberg et al. 2012). While it is possible that non-monotonic responses could potentially result in different effects following exposure at different time periods, this is not something that has been extensively studied and it is beyond the scope of the present review.