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The eyelid geckos (family Eublepharidae) include both species with temperature-dependent sex determination and species where genotypic sex determination (GSD) was suggested based on the observation of equal sex ratios at several incubation temperatures. In this study, we present data on karyotypes and chromosomal characteristics in 12 species (Aeluroscalabotes felinus, Coleonyx brevis, Coleonyx elegans, Coleonyx variegatus, Eublepharis angramainyu, Eublepharis macularius, Goniurosaurus araneus, Goniurosaurus lichtenfelderi, Goniurosaurus luii, Goniurosaurus splendens, Hemitheconyx caudicinctus, and Holodactylus africanus) covering all genera of the family, and search for the presence of heteromorphic sex chromosomes. Phylogenetic mapping of chromosomal changes showed a long evolutionary stasis of karyotypes with all acrocentric chromosomes followed by numerous chromosomal rearrangements in the ancestors of two lineages. We have found heteromorphic sex chromosomes in only one species, which suggests that sex chromosomes in most GSD species of the eyelid geckos are not morphologically differentiated. The sexual difference in karyotype was detected only in C. elegans which has a multiple sex chromosome system (X(1)X(2)Y). The metacentric Y chromosome evolved most likely via centric fusion of two acrocentric chromosomes involving loss of interstitial telomeric sequences. We conclude that the eyelid geckos exhibit diversity in sex determination ranging from the absence of any sexual differences to heteromorphic sex chromosomes, which makes them an interesting system for exploring the evolutionary origin of sexually dimorphic genomes.

Článek

Metabolic profile and sex hormone binding globulin (SHBG) in different reproductive phases of Czech women and their relations to weight, body composition and fat distribution

Physiological research. 2009 ; 58 (3) : 393-402.

ISSN 0862-8408
Medvik
Zdroj

In our study, 213 healthy Czech women aged 20 to 65 years were examined and divided into fully reproductive, premenopausal, menopausal and postmenopausal groups. In all subjects body composition was determined by classical anthropometry and metabolic profile was assessed. A total of 146 subjects completed 3-year longitudinal study. Total and LDL cholesterol increased and ratio HDL/total cholesterol decreased with age (p<0.001), most significantly in menopause. Triacylglycerols increased only up to menopause. HDL had a very slight trend to decrease in menopause and postmenopause. Fasting blood glucose level increased progressively (p<0.001), in postmenopause frequently exceeded normal range. Higher BMI, total fat mass and central fat indices were associated with higher total and LDL cholesterol, triacylglycerols, C-peptide, insulin and fasting blood glucose level (p<0.001; fasting blood glucose level to waist-to-hip ratio: p<0.01) and lower HDL cholesterol (p<0.001). Higher C-peptide and insulin were associated with lower HDL cholesterol and higher triacylglycerols (p<0.001). Fasting glucose correlated with LDL cholesterol (p<0.01). Higher SHBG was associated with higher HDL and lower LDL cholesterol (p<0.001). Hormone replacement treatment was related to lower fasting blood glucose level in postmenopausal women (p<0.01). Oral contraception is suggestive of a positive influence on lipid spectrum by increasing the ratio HDL/total cholesterol. Markers of lipid and carbohydrate metabolism are not only age-related, but they are also related to BMI, total fat mass and central fat indices. Therefore, preventive programs should be focused above all on menopausal women.