Cenostigma pyramidale: Ethnomedicinal Properties and Perspectives on A Legume Tree Highly Adapted to Semiarid ‘Caatinga’ Region
Mahendra Rai, Shandesh Bhattarai, Chistiane M. Feitosa in Ethnopharmacology of Wild Plants, 2021
Natural products are often less toxic than synthetic compounds. Despite this assumption, treatments with medicinal plants—as, for example, teas and infusions—can contain toxic substances that may have mutagenic and cytotoxic effects (Silva et al. 2015b). Toxicity is defined as an inherent property of compounds that cause harmful effects to exposed organisms over a specified time and concentration. The effects caused by these compounds include immobility, mortality, and inhibition of reproduction and reduction of cell growth of the test organism. As highlighted by Araujo et al. (2016), several steps and procedures are involved in the evaluation of possible cytotoxic, genotoxic, mutagenic and even carcinogenic processes of a given compound. Some plant-based phytochemicals, including some flavonoids and aromatic compounds (as estragole, safrole and methyl-eugenol), have mutagenic and carcinogenic potential (Rietjens et al. 2005). Van den Berg et al. (2011) listed compounds of plant origin that have such effects. Monoterpenes, coumarin, polyphenols, alkaloids and anthraquinones figure among them, besides those above mentioned.
Introduction to Toxicology
David Woolley, Adam Woolley in Practical Toxicology, 2017
The Dictionary of Toxicology (2nd edition, Macmillan Reference Ltd, 1998) defines toxicity as “the ability of a chemical to cause a deleterious effect when the organism is exposed to the chemical.” The Oxford English Dictionary indicates that toxicity is a “toxic or poisonous quality, especially in relation to its degree or strength.” These definitions contain a number of important concepts, such as deleterious effect, exposure of an organism, and degree or strength. They also suggest that toxicity is only seen following exposure to externally applied chemicals. In many ways, they throw up more questions than they answer. What is a deleterious effect or a toxic or poisonous quality? A simpler definition might be that it is an adverse change from normality, which may be irreversible; but this requires definition of adverse change and, crucially, of normality.
Acute toxicity test for the ethanolic extract of the white oyster mushroom
Ade Gafar Abdullah, Isma Widiaty, Cep Ubad Abdullah in Medical Technology and Environmental Health, 2020
An acute toxicity test was carried out using the proposed method. This method was a new method recommended for testing the acute toxicity of drugs or natural substances. Acute toxicity is an undesirable effect due to the administration of certain substances, in single or repeated doses, in a short time in the first 24 hours. A dosage curve for undesirable effects can also be seen using this method, in addition to assessing mortality. The method used was the Proposed (New) Method (Chinedu et al. 2013). Experimental animals were divided into several stages; the next stage depended on the results of the previous stage. The first or initial stage used four groups containing one mouse for each group. All four were given different doses and were seen 1 hour after administration and in periodic examinations for 24 hours to assess their mortality. If no deaths occurred, the testing could be continued in the second stage. The second stage involved three animals given a higher dose than in the first stage. Observation was carried out the same as in the previous stage. If no mortality took place, then the testing continued to the third stage using three mice. The maximum dose given was 5,000 mg/kg body weight (Chinedu et al. 2013).
Aesculus indica: an updated review on its pharmacognosy, phytochemistry and pharmacological profile
Published in Egyptian Journal of Basic and Applied Sciences, 2022
Neha Yadav, Aakash Partap Singh, Avtar Chand Rana, Sunil Kumar, Prabhjeet Kaur, Jitender Singh, Ashok Jangra, Dinesh Kumar
Traditionally, plant-based medicines have been used for treatments of various diseases. However, the uniformity of doses has not been specified scientifically, so the toxicity may induce, and prevention toxicity studies must be carried out to ensure the safety of the plant extract [22]. Toxicity generally refers to the interaction between biological systems and chemical compounds. Newly grown leaves and flowers are considered to be the toxic parts of this plant, and the seeds consist of poisonous saponins. Different parts of A. indica showed beneficial effects in both animals and human beings. The LD50 was found to be 10.6 mg/g body weight for chicks with one single dose of horse-chestnut seed extract and 10.7 mg/g body weight with hamster. Administration of A. indica for two consecutive days showed 6.5 mg/g LD50. Toxic manifestation of A. indica included fatigue, paralysis, coma and death [23]. Enlargement of pupils, diarrhea, consciousness disorder, thirst and flushing of the face were the other indications of consumption of a high amount of A. indica seeds. Only processed seeds were taken for medicinal occasions. In 1986, decoction of A. indica seed led to liver damage accompanied by another anaphylactic shock when given with intravenous injection [24].
Bioengineering lungs — current status and future prospects
Published in Expert Opinion on Biological Therapy, 2021
Vishal Swaminathan, Barry R. Bryant, Vakhtang Tchantchaleishvili, Taufiek Konrad Rajab
Subsequently, decellularization was begun using larger-scale organs [9,14]. In order to upscale the decellularization to a clinically usable size, the method first confirmed in rodents was subsequently tested in porcine, macaque, and human lungs [15,16]. Large-scale decellularized lung scaffolds have been confirmed to have a similar rate of architecture preservation and matrix composition to rat scaffolds, which supports the potential use of these constructs for clinical applications [11]. However, prior to use in humans, minimally acceptable criteria for a scaffold may be necessary. Firstly, the scaffolds should be nontoxic. Toxicity describes the harm to the recipient organism. Such harm can occur at the level of the cell, tissue, organ or organism. Secondly, the scaffolds should be biocompatible. Biocompatibility describes the absence of undesirable effects after implantation. Such undesirable effects can occur locally or systemically. Moreover, the scaffold should be conducive to the growth of many reintroduced cell types, such as epithelium, endothelium and resident macrophages without inhibiting their function or altering their phenotype. Importantly, human cells thrived equally on porcine and human scaffolds. If such xenogenic scaffolds are proven non-immunogenic in human patients, this could open an unlimited supply of scaffolds derived from pigs.
Pseudotumor Cerebri Syndrome with Resolution After Discontinuing High Vitamin A Containing Dietary Supplement: Case Report and Review
Published in Neuro-Ophthalmology, 2018
Jason T. Chisholm, Michelle M. Abou-Jaoude, Amy B. Hessler, Padmaja Sudhakar
In our case, the patient had been taking a weight loss supplement, containing 1500 IU of vitamin A per capsule, twice daily for a year. We believe that chronic ingestion over many months led to cumulative toxicity. Her papilledema and symptoms started improving with discontinuation of the supplement and resolved by six months, similar to other cases linked to vitamin A.27 Although the vitamin A level seems lower, we hypothesize that PTCS in this case could be a result of two factors. First, the level of vitamin A intake required for toxicity may be lower than previously reported, which could be especially true for cases of chronic daily use. Individual tolerances to different amounts of vitamin A ingested on a chronic basis have not yet been adequately studied,32 and better understanding on the subject could provide insight into factors that result in chronic vitamin A toxicity. Therefore, in cases of chronic vitamin A intoxication, it may be prudent to characterize vitamin A consumption as a product of duration, rather than simply daily values, to determine likelihood of toxicity.
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