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    The relationship between hair metabolites, air pollution exposure and gestational diabetes mellitus: A longitudinal study from pre-conception to third trimester.
    (Frontiers Media S.A., 2022-12-02) Chen X; Zhao X; Jones MB; Harper A; de Seymour JV; Yang Y; Xia Y; Zhang T; Qi H; Gulliver J; Cannon RD; Saffery R; Zhang H; Han T-L; Baker PN; Zhou N
    BACKGROUND: Gestational diabetes mellitus (GDM) is a metabolic condition defined as glucose intolerance with first presentation during pregnancy. Many studies suggest that environmental exposures, including air pollution, contribute to the pathogenesis of GDM. Although hair metabolite profiles have been shown to reflect pollution exposure, few studies have examined the link between environmental exposures, the maternal hair metabolome and GDM. The aim of this study was to investigate the longitudinal relationship (from pre-conception through to the third trimester) between air pollution exposure, the hair metabolome and GDM in a Chinese cohort. METHODS: A total of 1020 women enrolled in the Complex Lipids in Mothers and Babies (CLIMB) birth cohort were included in our study. Metabolites from maternal hair segments collected pre-conception, and in the first, second, and third trimesters were analysed using gas chromatography-mass spectrometry (GC-MS). Maternal exposure to air pollution was estimated by two methods, namely proximal and land use regression (LUR) models, using air quality data from the air quality monitoring station nearest to the participant's home. Logistic regression and mixed models were applied to investigate associations between the air pollution exposure data and the GDM associated metabolites. RESULTS: Of the 276 hair metabolites identified, the concentrations of fourteen were significantly different between GDM cases and non-GDM controls, including some amino acids and their derivatives, fatty acids, organic acids, and exogenous compounds. Three of the metabolites found in significantly lower concentrations in the hair of women with GDM (2-hydroxybutyric acid, citramalic acid, and myristic acid) were also negatively associated with daily average concentrations of PM2.5, PM10, SO2, NO2, CO and the exposure estimates of PM2.5 and NO2, and positively associated with O3. CONCLUSIONS: This study demonstrated that the maternal hair metabolome reflects the longitudinal metabolic changes that occur in response to environmental exposures and the development of GDM.
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    Werewolf, There Wolf: Variants in Hairless Associated with Hypotrichia and Roaning in the Lykoi Cat Breed.
    (MDPI (Basel, Switzerland), 2020-06-22) Buckley RM; Gandolfi B; Creighton EK; Pyne CA; Bouhan DM; LeRoy ML; Senter DA; Gobble JR; Abitbol M; Lyons LA; 99 Lives Consortium
    A variety of cat breeds have been developed via novelty selection on aesthetic, dermatological traits, such as coat colors and fur types. A recently developed breed, the lykoi (a.k.a. werewolf cat), was bred from cats with a sparse hair coat with roaning, implying full color and all white hairs. The lykoi phenotype is a form of hypotrichia, presenting as a significant reduction in the average numbers of follicles per hair follicle group as compared to domestic shorthair cats, a mild to severe perifollicular to mural lymphocytic infiltration in 77% of observed hair follicle groups, and the follicles are often miniaturized, dilated, and dysplastic. Whole genome sequencing was conducted on a single lykoi cat that was a cross between two independently ascertained lineages. Comparison to the 99 Lives dataset of 194 non-lykoi cats suggested two variants in the cat homolog for Hairless (HR) (HR lysine demethylase and nuclear receptor corepressor) as candidate causal gene variants. The lykoi cat was a compound heterozygote for two loss of function variants in HR, an exon 3 c.1255_1256dupGT (chrB1:36040783), which should produce a stop codon at amino acid 420 (p.Gln420Serfs*100) and, an exon 18 c.3389insGACA (chrB1:36051555), which should produce a stop codon at amino acid position 1130 (p.Ser1130Argfs*29). Ascertainment of 14 additional cats from founder lineages from Canada, France and different areas of the USA identified four additional loss of function HR variants likely causing the highly similar phenotypic hair coat across the diverse cats. The novel variants in HR for cat hypotrichia can now be established between minor differences in the phenotypic presentations.
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    A novel and environmentally friendly method for preserving and depilating sheepskin : comprehensive physical, biochemical and molecular analyses : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Biochemistry at Massey University, Manawatu, New Zealand
    (Massey University, 2021) Tu, Yi-Hsuan
    The first step of leather processing, depilation – in other words, removing hair from skins – accounts for one-third of the leather-making industrial waste due to the production of sulfide and alkaline water waste from the process. This study describes a method that preserves and depilates unwashed sheepskins using milk or milk by-products, including whey and permeate. It doesn’t require the use of harsh chemicals or temperature control, and results in skin that is ready to be tanned. In order to evaluate the products of this process, the depilated skin surface was evaluated not only by eye, but with scanning and transmission electron microscopy (SEM and TEM) which showed there was no apparent damage to the grain or fraying of the collagen bundles. The depilated skin was also processed to leather which was subjected to tear, tensile and shrinkage measurements which were shown to be almost identical to leathers made using the traditional process. Quantitative biochemical analyses, including collagen quantitation, collagen crosslink analysis and glycosaminoglycan (GAG) analysis of sheepskins depilated with this process showed no significant differences in both collagen, and collagen crosslink concentrations in contrast to the 10-fold increase seen in the GAG concentration. A quantitative proteomic analysis showed there was a higher retention of proteins found in the basement membrane of the skin, supporting the observation that permeate depilated skins were smoother than their sulfide depilated counterparts and produced leather with a superior surface. It also showed the loss of specific proteins around the hair follicle, hinting at a possible mechanism for depilation. To further investigate this a microbiological survey of the process was conducted. Traditional culturing methods were used to isolate and identify microorganisms present in the depilation solution after the wool had been removed. Two bacterial species (Lactococcus lactis and Lactobacillus plantarum) and two fungal species (Geotrichum candidum and Yarrowia lipolytica), were routinely identified, all of which are known to secrete a number of hydrolytic enzymes and antimicrobial compounds. This was followed by a metagenomic study of changes in the microbial community over the time course of the depilation. Although there were only 13 dominant bacterial genera identified during this study, the biggest change was a concomitant increase in the relative abundance of Lactococcus lactis that matched the decrease in Acinetobacter sp. by the end of the depilation treatment, controlling the proliferation of other putrefying organisms. In conclusion, this preliminary study has paved the way for the development of a depilation process that is kind to the environment, but more research is needed to investigate its potential use with other animal skins.