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Drugs in pregnancy and lactation
Published in Evelyne Jacqz-Aigrain, Imti Choonara, Paediatric Clinical Pharmacology, 2021
Evelyne Jacqz-Aigrain, Imti Choonara
The purpose of embryo-fetal toxicity studies and pre/postnatal toxicity studies is to determine if developmental toxicity appears at a lower, similar, or higher dose than does maternal toxicity. Minimal toxicity should be observed in dams at the highest dose level tested. In most cases, a 10–15% decrease in body weight gain in rodents is considered to be a good indication of minimal maternal toxi-city. In rabbits, a prolonged decrease in food consumption should be considered a better indicator of maternal toxicity, as it is more closely and more rapidly related to poor health conditions than body weight changes [6]. High levels of maternal toxicity can induce bias in the interpretation of the study results, because such toxicity can result in nonspecific developmental toxicity. Thus, when there is evidence of severe maternal toxicity, these experimental groups should be discounted and the interpretation should be focused on a lower highest dose.
Consumer Safety Considerations of Cosmetic Preservation*
Published in Philip A. Geis, Cosmetic Microbiology, 2020
Corie A. Ellison, Alhaji U. N’jai, Donald L. Bjerke
Since the developmental toxicity endpoint is very complex, there has yet to be any validated in vitro assays that can address this endpoint. One potential alternative approach to cover this endpoint is to rely on existing historical developmental toxicity data as illustrated by Structural Activity Relationship and/or decision tree–based approaches (42,43).
Environmental Exposures and Reproduction *
Published in Michele Kiely, Reproductive and Perinatal Epidemiology, 2019
The fields of developmental and reproductive toxicology have undergone great growth in the years since 1961 when thalidomide was first identified as a developmental toxicant. In the early years, teratogens (i.e., agents that cause structural malformations in offspring exposed during critical developmental times) were of primary concern. More recently, the term “teratology” has been replaced with the more broadly defined term, “developmental toxicology”: “the study of adverse effects on the developing organism that may result from exposure prior to conception (either parent), during prenatal development, or postnatally to the time of sexual maturation. Adverse developmental effects may be detected at any point in the life span of the organism. The major manifestations of developmental toxicity include: (1) death of the developing organism, (2) structural abnormality, (3) altered growth, and (4) functional deficiency.”4
Induction of developmental toxicity and cardiotoxicity in zebrafish embryos/larvae by acetyl-11-keto-β-boswellic acid (AKBA) through oxidative stress
Published in Drug and Chemical Toxicology, 2022
Liwen Han, Qing Xia, Lei Zhang, Xuanming Zhang, Xiaobin Li, Shanshan Zhang, Lizhen Wang, Changxiao Liu, Kechun Liu
The developmental toxicity assay was performed as previously described (Xia et al. 2017). In brief, normal embryos at 4 hpf were selected under a SZX16 stereo microscope (Olympus, Tokyo, Japan) and randomly transferred to preconditioned 24-well plates (10 embryos per well) (Corning, New York, USA) refilled with either exposure solutions or fish water to reach a final volume of 2 mL per well. A pre-experiment was performed to determine none lethal and total lethal concentrations. Finally, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 μM of AKBA were selected as the exposure concentrations to establish a lethality curve. The mortality of zebrafish embryos was recorded at 24, 48, 72 and 96 hpf. Morphological abnormalities in development were examined at 24, 48, 72 and 96 hpf. Hatching rate at 72 and 96 hpf was recorded. The body length at 96 hpf was measured using Image-Pro Plus (Media Cybernetics, Bethesda, USA).
In silico evaluation of multispecies toxicity of natural compounds
Published in Drug and Chemical Toxicology, 2021
Sripriya N., Ranjith Kumar M., Ashwin Karthick N., Bhuvaneswari S., Udaya Prakash N. K.
Bioaccumulation factor is the ratio of the concentration of a chemical in fish due to absorption via the respiratory surface with respect to water at steady state. In general, a compound is termed bioaccummulative, if its BF value is greater than 2000 and very bioaccummulative if its value is greater than 5000 (Burden et al. 2014). In the present study, the bioaccumulation factor for all the compounds was less than 2000, and hence, non-bioaccummulative in nature. Developmental toxicity defines whether a particular chemical causes any effect that hinders normal development, both before and after birth. Most of the compounds i.e., 15 out of 27 studied from the plants – C. angustifolium, C. carandas, and E. oxypetalum were developmental toxicants. Compounds that are positive to Ames mutagenicity test are regarded as potential carcinogens (Griffiths et al. 2000). The non-mutagenicity of the 27 compounds studied, except for Dasycarpidan-1-methanol, acetate (ester), suggests that the compounds can be explored in different industries.
Safety assessment of cerium oxide nanoparticles: combined repeated-dose toxicity with reproductive/developmental toxicity screening and biodistribution in rats
Published in Nanotoxicology, 2020
Jinsoo Lee, Ji-Seong Jeong, Sang Yun Kim, Seung-Jin Lee, Young-Jun Shin, Wan-Jung Im, Sung-Hwan Kim, Kwangsik Park, Eun Ju Jeong, Sang-Yoon Nam, Wook-Joon Yu
Combined repeated-dose toxicity with reproductive/developmental toxicity screening tests are required by OECD test guidelines for testing chemicals that are reviewed in light of scientific progress by the various regulatory authorities (OECD 1996). This toxicity study is needed for industrial chemicals with a production or import level of more than 10 tonnage per year according to the European Registration, Evaluation, Authorization and Restriction of Chemicals (EU REACH) legislation (Beekhuijzen et al. 2014). This study design is able to assess various developmental and reproductive toxicity endpoints as well as general toxicity endpoints in subacute toxicity studies. Thus far, since controversial toxicity results have been obtained with CeO2 NPs in previous in vitro and in vivo studies, the combined repeated-dose toxicity with reproductive/developmental toxicity screening test could be considered one of the most appropriate toxicity studies to evaluate the potential effects of CeO2 NPs on general functions as well as developmental and reproductive functions. In addition, we also analyzed the internal systemic distribution of CeO2 NPs in major organs (blood, liver, lungs and kidneys) of parental animals and their pups after repeated oral exposure.