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Chromosome Abnormalities in Human Pregnancy Loss
Published in Carlos Simón, Carmen Rubio, Handbook of Genetic Diagnostic Technologies in Reproductive Medicine, 2022
For most purposes, karyotypic analysis provides an unambiguous approach to the identification of numerical or major structural abnormalities. However, in the instance of SABs, fetally derived tissue may be scant, unviable, or difficult to culture. Coupled with the presence of maternally derived placental material, artifactual 46,XX results are a common complication of SAB studies. The consequences of maternal contamination are readily apparent from the results of cytogenetic studies of SABs (Table 28.2). For example, the sex ratio among euploid samples (i.e., 46,XY; 46,XX) varies by an order of magnitude among the different studies, from nearly 3:1 to 0.3:1, presumably reflecting differences in the likelihood of including maternal tissue samples. Accordingly, the overall proportion of chromosome abnormalities is also remarkably variable among the different studies, with the lowest chromosome abnormality rates typically tracking with the lowest sex ratios.
Paper 4
Published in Amanda Rabone, Benedict Thomson, Nicky Dineen, Vincent Helyar, Aidan Shaw, The Final FRCR, 2020
Amanda Rabone, Benedict Thomson, Nicky Dineen, Vincent Helyar, Aidan Shaw
Turner syndrome is a chromosomal abnormality occurring only in females. It is associated with cardiovascular anomalies including hypoplastic left heart and aortic coarctation and renal anomalies including ectopia and horseshoe kidney. Radiographs of the hand may show shortened third and fourth metacarpals, Madelung deformity, carpal coalition and narrowing of the scapholunate angle. The other findings listed in the question are not seen in Turner syndrome.
Common Tips on Communication
Published in Justin C Konje, Complete Revision Guide for MRCOG Part 3, 2020
First, you will need to have a more detailed scan performed, especially by experts such as fetal medicine consultants, so as to identify some of these abnormalities. Because of an increased risk of chromosomal abnormalities (up to 30% of these babies will have a chromosome abnormality), you will be offered a test known as an amniocentesis (taking a small amount of fluid around the baby) to help determine if the baby’s chromosomes are normal or not.
Clarifying the Blurry Boundaries between Research and Clinical Care
Published in The American Journal of Bioethics, 2022
Given the blurring of the lines between clinical care and research in the field of precision medicine, can the ACMG justify such a bright line? Other investigators support it. The Electronic Medical Records and Genomics (eMERGE) Network funded by the National Human Genome Research Institute (NHGRI) convened a return of results oversight committee to identify potentially returnable research results (NHGRI 2020). Fullerton and colleagues reported that the oversight committee was unanimous about the importance of returning chromosomal abnormalities in the clinical setting “even if the finding was incidental,” although there was wide variability in perspective in the research setting (Fullerton et al. 2012). Part of the reluctance is due to the context in which the findings are uncovered, the lack of relationship between researcher and participant, and the lack of resources (financial, appropriate counseling skills, and time) for appropriate follow-up in the research setting. The reluctance may be magnified by the fact that Klinefelter Syndrome is a sex chromosome abnormality. If the young man had been diagnosed in childhood, there would have been time to ensure that he received medical and psychosocial support and treatment in a developmentally appropriate way. What degree of responsibility are the researchers willing to assume to ensure that the disclosure is provided in such a way as to maximize benefits and minimize potential harms?
Differences in foot dimensions between children and adolescents with and without Down syndrome
Published in Disability and Rehabilitation, 2022
Nirmeen M. Hassan, Andrew K. Buldt, Nora Shields, Karl B. Landorf, Hylton B. Menz, Shannon E. Munteanu
Down syndrome is a common chromosomal abnormality that results in the trisomy of chromosome 21 [1]. It is associated with a number of orthopaedic anomalies and musculoskeletal disorders [2]. Approximately 20 to 27% of people with Down syndrome experience musculoskeletal disorders, and foot deformities make up 30% of all reported orthopaedic complaints [3]. Structural anomalies such as hallux valgus deformity and flat feet are the two most commonly reported in the literature [4–6]. However, other structural anomalies that may cause foot problems include digital deformities, bony deformities of the forefoot [4], hallucal cleft, isolated calcaneal valgus [4] and a plantarflexed first ray. Several of these structural anomalies are thought to occur secondary to higher body mass index [7], muscular hypotonia [8], ankle instability [9] as well as ligamentous laxity [10] – all of which are associated with Down syndrome. These structural anomalies may have a negative impact on gait, engaging in daily activities [11] and footwear-fitting.
Do steviol glycosides affect the oxidative and genotoxicity parameters in BALB/c mice?
Published in Drug and Chemical Toxicology, 2022
Şemsi Gül Yılmaz, Aslı Uçar, Serkan Yılmaz
Our findings indicated that the SG doses used apparently did not have in vivo genotoxic effects but did exerted weak genotoxicity which is most probably related to the increased oxidative damage. The biochemical data obtained in this study was consistent with the chromosome abnormality results. However, SG had mitogenic effects in all doses. The consumption of stevia is increasing on a daily basis because it is classed as a natural sweetener and considered safe by some researchers and authorities. In addition to this study, which is among the pioneering studies to determine the safety of SG consumption, it is necessary that further investigations are conducted to clarify the reliability of SG compounds, particularly in the field of research on tumor development, and thus determine if the intake of stevia by consumers should be limited or not. Such future investigations should be conducted using different study organisms.