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Harv Rev Psychiatry,
2012]
This article addresses the classic enigma about schizophrenia (SZ). The disease occurs with a lifetime prevalence of 1%, 80% of which is attributable to genetic factors. Females with SZ produce 50% as many children as normals, and males with SZ produce 25%. Genetic factors responsible for SZ should behave like lethal genes. Yet the prevalence of SZ remains around 1% throughout the world. How can that be? Additionally, CATIE concluded that the response of each individual with SZ to treatment with antipsychotic agents (effectiveness, side-effect profile, or long-term prognosis) cannot be predicted. Every case seems to be unique. Several recent publications have reported increased frequencies of single-nucleotide polymorphisms (SNPs) and of copy-number variants (CNVs) containing large regions of DNA in patients with SZ. These genetic perturbations often include neurodevelopmental genes. The overwhelming majority of SNPs and CNVs are post-fertilization mutations, occurring in somatic tissue, not germinal tissue. These mutations are a normal aspect of somatic cell division but occur more frequently in patients with SZ. Somatic mutations are not passed on to subsequent generations and therefore cannot account for the inheritance of SZ. Our speculation is that the genetic platform for SZ is the gene or genes that increase the number of de novo mutations in patients with SZ. We argue that balanced polymorphism is the most plausible hypothesis to account for the preservation of non-adaptive genes in nature-and, in particular, in SZ. Maladaptive genes in different combinations can confer increased fitness to the entire population, thus insuring their preservation in the gene pool. Somatic mutations explain both the sporadic occurrence of SZ within families and the wide variations in phenotypic expression of SZ. Increased frequency of somatic mutations may confirm greater overall fitness via balanced polymorphism to explain the maintenance of the SZ gene or genes within the human population.
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J Ethnopharmacol,
2001]
Five aqueous extracts from three plant species, i.e., dried husks (HX), dried seeds (SX) and dried leaves (LX) of Xylocarpus granatum (Meliaceae), dried stems (ST) of Tinospora crispa (Menispermaceae) and dried leaves (LA) of Andrographis paniculata (Acanthaceae) were tested in vitro against adult worms of subperiodic Brugia malayi. The relative movability (RM) value of the adult worms over the 24-h observation period was used as a measure of the antifilarial activity of the aqueous extracts. SX extract of X. granatum demonstrated the strongest activity, followed by the LA extract of A. paniculata, ST extract of T. crispa, HX extract and LX extract of X. granatum.
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Chemosphere,
2021]
Research on the environmental impact of plastics, especially on the effect of microplastics (MPs), has become a priority issue in recent years, mainly in terrestrial ecosystems where there is a lack of studies. This work aims to assess the impact of two types of polyethylene MPs, white microbeads (W) and fluorescent blue microbeads (FB), and their interactions with two contaminants, ibuprofen (Ib) and simazine (Sz), on different organisms. A set of bioassays for Vibrio fischeri, Caenorhabditis elegans and Lactuca sativa was carried out, which helped to establish the ecotoxicological impact of those pollutants. C.elegans showed the least sensitivity, while V.fischeri and L.sativa showed a high toxicological response to MPs alone. We found that W and FB induced an inhibition of 27% and 5.79%, respectively, in V.fischeri, and the growth inhibition rates were near 70% in L.sativa for both MPs. MPs exhibited a potential role as contaminant vectors in V.fischeri since the inhibition caused by W-Ib or W-Sz complexes was near 39%. The W-Sz complex significantly reduced leaf development in L.sativa, and a reduction of 30% in seed germination was detected when the complex FB-Sz was tested. This study reveals the importance of designing a complete set of analyses with organisms from different trophic levels, considering the great variability in the effects of MPs and the high number of relevant factors.
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Life Sci Space Res (Amst),
2014]
Recent advances in the field of molecular biology have demonstrated that small non-coding microRNAs (miRNAs) have a broad effect on gene expression networks and play a key role in biological responses to environmental stressors. However, little is known about how space radiation exposure and altered gravity affect miRNA expression. The "International Space Biological Experiments" project was carried out in November 2011 by an international collaboration between China and Germany during the Shenzhou-8 (SZ-8) mission. To study the effects of spaceflight on Caenorhabditis elegans (C. elegans), we explored the expression profile miRNA changes in space-flown C. elegans. Dauer C. elegans larvae were taken by SZ-8 spacecraft and experienced the 16.5-day shuttle spaceflight. We performed miRNA microarray analysis, and the results showed that 23 miRNAs were altered in a complex space environment and different expression patterns were observed in the space synthetic and radiation environments. Most putative target genes of the altered miRNAs in the space synthetic environment were predicted to be involved in developmental processes instead of in the regulation of transcription, and the enrichment of these genes was due to space radiation. Furthermore, integration analysis of the miRNA and mRNA expression profiles confirmed that twelve genes were differently regulated by seven miRNAs. These genes may be involved in embryonic development, reproduction, transcription factor activity, oviposition in a space synthetic environment, positive regulation of growth and body morphogenesis in a space radiation environment. Specifically, we found that cel-miR-52, -55, and -56 of the miR-51 family were sensitive to space environmental stressors and could regulate biological behavioural responses and neprilysin activity through the different isoforms of T01C4.1 and F18A12.8. These findings suggest that C. elegans responded to spaceflight by altering the expression of miRNAs and some target genes that function in diverse regulatory pathways.
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Chemosphere,
2021]
Microplastics (MPs), pharmaceuticals and pesticides are emerging pollutants with proposed negative impacts on the environment. Rising interest in investigations of MPs is likely related to their potential to accumulate in agricultural systems as the base of the food chain. We applied an integrated approach using classic bioassays and molecular methods to evaluate the impact associated with a mixture of three types of polyethylene (PE) microbeads, namely, white (W), blue (B), and fluorescent blue (FB), and their interactions with pollutants (OCs), including ibuprofen (IB), sertraline (STR), amoxicillin (AMX) and simazine (SZ), on different soil organisms. PE-MPs exhibited different abilities for the adsorption of each OC; W selectively adsorbed higher amounts of SZ, whereas B and FB preferably retained AMX. Standard soil was artificially contaminated with OCs and MPs (alone or combined with OCs) and incubated for 30 days. The presence of MPs or MPs and OCs (MIX) in soil did not produce any effect on Caenorhabditis elegans endpoint growth, reproduction, or survival. Inhibition of leaf growth in Zea mays was detected, but this negative effect declined over time, while the inhibition of root growth increased, especially when OCs (32%) or MIX (47%) were added. Moreover, the expression of the antioxidant genes CAT 1, SOD-1A and GST 1 on plants was affected by the treatments studied. The addition of MPs or MIX significantly affected the soil bacterial phylogenetic profile, which selectively enriched members of the bacterial community (particularly Proteobacteria). The predicted functional profiles of MP/MIX samples indicated a potential impact on the carbon and nitrogen cycle within the soil environment. Our results indicate that MPs and their capability to act as pollutant carriers affect soil biota; further studies should be carried out on the bioavailability of OCs adsorbed by microplastics and how long it takes to leach these OCs into different organisms and/or ecosystems.