Canadian Ultralight Accidents in Water (1990 to 2020).

Recently, an analysis of Canadian seaplane accidents terminating in water (1995-2019) was conducted, but ultralight water accidents were excluded due to differences from general aviation operations. This is the first literature that reports a series of ultralight accidents that occurred in water. The purpose of this paper is to identify the circumstances surrounding ultralight water accidents in Canada and to identify actions with the potential to improve survival.

Survival from Canadian Seaplane Water Accidents: 1995 to 2019.

Each year in Canada, there are a number of pilots and passengers who die in seaplane water accidents. A study examining the human factors and fatality rates associated with these accidents was conducted. Seaplane water accident investigations by the Transportation Safety Board of Canada (TSB) between 1995 and 2019 were reviewed.

Partitioning of [methyl-3H]methionine to methylated products and protein is altered during high methyl demand conditions in young Yucatan miniature pigs.

Methionine is the main source of methyl groups that are partitioned to synthesize various methylated products including creatine, phosphatidylcholine (PC), and methylated DNA. Whether increased methylation of 1 product can divert methionine from protein synthesis or other methylation products was the aim of this experiment. We used an excess of guanidinoacetate (GAA) to synthesize creatine to create a higher demand for available methyl groups in normal-weight (NW) (n = 10) and intrauterine growth-restricted (IUGR) (n = 10) piglets.

Intrauterine growth restriction leads to changes in sulfur amino acid metabolism, but not global DNA methylation, in Yucatan miniature piglets.

Intrauterine growth restriction (IUGR), in both animals and humans, has been linked to metabolic syndrome later in life. There has been recent evidence that perturbations in sulfur amino acid metabolism may be involved in this early programming phenomenon. Methionine is the precursor for cellular methylation reactions and for the synthesis of cysteine.

Expression of the dnmt3 genes in zebrafish development: similarity to Dnmt3a and Dnmt3b.

The zebrafish differs from mammals in that they have six dnmt3 genes as opposed to the two that can produce a catalytically active protein in mammals. Zebrafish also do not show evidence of genomic imprinting and lack the Dnmt3l gene necessary to that process in mammals. As such, they offer a unique opportunity to compare the two genetic situations in order to define the roles of the multiple genes in developmental gene methylation.

Immunological detection of changes in genomic DNA methylation during early zebrafish development.

DNA methylation reprogramming, the erasure of DNA methylation patterns shortly after fertilization and their reestablishment during subsequent early development, is essential for proper mammalian embryogenesis. In contrast, the importance of this process in the development of non-mammalian vertebrates such as fish is less clear. Indeed, whether or not any widespread changes in DNA methylation occur at all during cleavage and blastula stages of fish in a fashion similar to that shown in mammals has remained controversial.

Novel splice variants associated with one of the zebrafish dnmt3 genes.

Background: DNA methylation and the methyltransferases are known to be important in vertebrate development and this may be particularly true for the Dnmt3 family of enzymes because they are thought to be the de novo methyltransferases. Mammals have three Dnmt3 genes; Dnmt3a, Dnmt3b, and Dnmt3L, two of which encode active enzymes and one of which produces an inactive but necessary cofactor. However, due to multiple promoter use and alternative splicing there are actually a number of dnmt3 isoforms present.

Variations in DNA (cytosine-5)-methyltransferase-1 expression during oogenesis and early development of the zebrafish.

We report the determination of zebrafish DNA (cytosine-5-) methyltransferase ( dnmt-1) temporal and spatial patterns of expression in gonadal tissues and during early development. Only one dnmt-1 message of around 5 kb was observed in all tissues examined and its levels were highest in gonadal tissues. During the course of oogenesis, early oocytes contain significant amounts of dnmt-1 transcript while message abundance declines as oocytes mature.