d-Glucuronolactone attenuates para-xylene-induced defects in neuronal development and plasticity in Xenopus tectum in vivo

Exhaled breath is feasible for mild cognitive impairment detection: A diagnostic study with portable micro-gas chromatography

BackgroundMild cognitive impairment (MCI) is an important prodromal stage of Alzheimer's disease (AD), affecting 69 million individuals worldwide. At present, there is a lack of a community-applicable tool for MCI screening. Exhaled breath volatile organic compounds (VOCs) have been used to distinguish MCI from cognitively normal (CN) individuals only in small sample size studies and the efficacy has not been compared with blood biomarkers.ObjectiveThis diagnostic study aimed to assess the feasibility of using exhaled breath VOCs detection by a portable micro-gas chromatography (μGC) device as a screening tool to discriminate MCI from CN individuals in a community population.MethodsA detection model was developed and optimized from five distinct machine learning algorithms based on the differential VOCs between 240 MCI and 241 CN individuals. Among these 481 participants, five plasma biomarkers were measured in 397 individuals (166 MCI and 231 CN).ResultsThe final model (481 individuals) incorporating eight differential VOCs showed good performance with an area under the receiver-operating characteristic curve (AUC) of 0.84 (95% confidence interval (95% CI): 0.83-0.85). The AUC of the VOC model (0.80, 95% CI: 0.69-0.90) was higher than that of the plasma model (0.77, 95% CI: 0.65-0.88) (397 individuals).ConclusionsThe detection of exhaled breath VOCs by a portable μGC device is feasible for MCI screening in community populations, potentially facilitating early detection and intervention strategies for individuals at high risk.

Xenopus laevis (Daudin, 1802) as a Model Organism for Bioscience: A Historic Review and Perspective

In vitro systems have been mainly promoted by authorities to sustain research by following the 3Rs principle, but continuously increasing amounts of evidence point out that in vivo experimentation is also of extreme relevance. Xenopus laevis, an anuran amphibian, is a significant model organism in the study of evolutionary developmental biology, toxicology, ethology, neurobiology, endocrinology, immunology and tumor biology; thanks to the recent development of genome editing, it has also acquired a relevant position in the field of genetics. For these reasons, X. laevis appears to be a powerful and alternative model to the zebrafish for environmental and biomedical studies. Its life cycle, as well as the possibility to obtain gametes from adults during the whole year and embryos by in vitro fertilization, allows experimental studies of several biological endpoints, such as gametogenesis, embryogenesis, larval growth, metamorphosis and, of course, the young and adult stages. Moreover, with respect to alternative invertebrate and even vertebrate animal models, the X. laevis genome displays a higher degree of similarity with that of mammals. Here, we have reviewed the main available literature on the use of X. laevis in the biosciences and, inspired by Feymann's revised view, "Plenty of room for biology at the bottom", suggest that X. laevis is a very useful model for all possible studies.

Xenopus in revealing developmental toxicity and modeling human diseases

The Xenopus model offers many advantages for investigation of the molecular, cellular, and behavioral mechanisms underlying embryo development. Moreover, Xenopus oocytes and embryos have been extensively used to study developmental toxicity and human diseases in response to various environmental chemicals. This review first summarizes recent advances in using Xenopus as a vertebrate model to study distinct types of tissue/organ development following exposure to environmental toxicants, chemical reagents, and pharmaceutical drugs. Then, the successful use of Xenopus as a model for diseases, including fetal alcohol spectrum disorders, autism, epilepsy, and cardiovascular disease, is reviewed. The potential application of Xenopus in genetic and chemical screening to protect against embryo deficits induced by chemical toxicants and related diseases is also discussed.

Wnt/β-Catenin Signaling in Neural Stem Cell Homeostasis and Neurological Diseases

Neural stem/progenitor cells (NSCs) maintain the ability of self-renewal and differentiation and compose the complex nervous system. Wnt signaling is thought to control the balance of NSC proliferation and differentiation via the transcriptional coactivator β-catenin during brain development and adult tissue homeostasis. Disruption of Wnt signaling may result in developmental defects and neurological diseases. Here, we summarize recent findings of the roles of Wnt/β-catenin signaling components in NSC homeostasis for the regulation of functional brain circuits. We also suggest that the potential role of Wnt/β-catenin signaling might lead to new therapeutic strategies for neurological diseases, including, but not limited to, spinal cord injury, Alzheimer's disease, Parkinson's disease, and depression.