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Child and Adolescent Psychiatry and... Jan 2024Gender incongruence can often manifest itself from early childhood [Olson KR, Gülgöz S. Child Dev Perspect. 2018;12:93-7. https://doi.org/10.1111/cdep.12268 ] with a...
BACKGROUND
Gender incongruence can often manifest itself from early childhood [Olson KR, Gülgöz S. Child Dev Perspect. 2018;12:93-7. https://doi.org/10.1111/cdep.12268 ] with a significant psychological impact, altering social and school dynamics without the appropriate care.[Tordoff DM, et al. JAMA Netw Open. 2022;5(2): e220978. https://doi.org/10.1001/jamanetworkopen.2022.0978 ] Early identification and gender-affirming care are essential to reduce adverse mental health outcomes, such as depression and self-harm [Tordoff DM, et al. JAMA Netw Open. 2022;5(2): e220978. https://doi.org/10.1001/jamanetworkopen.2022.0978 ].This study aims to analyze characteristics and to estimate relative frequencies of gender incongruence in a population of children and adolescents receiving gender-affirming care at a high-complexity university hospital located in the third largest city in Colombia.
METHODS
This was a retrospective descriptive study of patients under 18 with gender incongruence that received gender-affirming care between January 2018 and June 2022 at Fundacion Valle del Lili in Cali, Colombia. Sociodemographic and clinical characteristics of 43 patients were assessed, as well as the relative frequencies of gender incongruence. Data analysis was performed with the statistical package STATA®. To determine significant differences between the characteristics of the patients who participated in the study, the Mann‒Whitney U test was performed for numerical variables with non-parametric distribution, while either Pearson's Chi-2 test or Fisher's exact test was performed for categorical variables.
RESULTS
For every ten individuals assigned female at birth, who manifested gender incongruence, there were eight assigned male at birth. The median age of onset of gender incongruence was ten years (IQR: 5-13 years), and the median time elapsed between the reported onset of gender incongruence and the first consultation with a multidisciplinary gender-affirming team was three years (IQR: 1-10 years). The frequency of transgender identity was notable in participants with ages between 15 and 17 years. Depressive symptoms, anxiety, and psychotropic drug use were significantly higher in individuals assigned female at birth. Among 25 individuals assigned female at birth who participated in this study, 60% self-recognized as transgender men.18 individuals assigned male at birth, 67% self-recognized as transgender women. The most frequent treatment was a referral to mental health services (46.51%).
CONCLUSION
Based on the cohort of our study, we can conclude that patients consult for gender-affirming treatment 3 years after the onset of gender incongruence. Anxiety and depression were higher in individuals assigned female at birth. Additionally, they presented at a later stage of sexual maturation, reducing the possibility of using puberty blockers.
PubMed: 38172957
DOI: 10.1186/s13034-023-00689-6 -
Ecotoxicology and Environmental Safety Jan 2024Tetrachlorobisphenol A (TCBPA), a halogenated flame retardant and endocrine disruptor, has been detected in human urine and serum. While previous research has shown its...
Tetrachlorobisphenol A (TCBPA), a halogenated flame retardant and endocrine disruptor, has been detected in human urine and serum. While previous research has shown its impact on the reproductive system, investigations into its mechanisms during puberty remain limited. This study aims to explore the effects of TCBPA on Leydig cells in adolescent mice and potential underlying mechanisms. Male C57 mice of age 28 days were gavaged with 50, 100, and 200 mg/kg/day for 28 days. TCBPA did not alter body weight and testis weight but lowered testosterone levels at 100 and 200 mg/kg and reduced sperm count in the epididymis at 200 mg/kg. TCBPA lowered Leydig cell number at 200 mg/kg while it downregulated key Leydig cell gene (Lhcgr, Scarb1, Cyp11a1, Cyp17a1, Hsd3b6, Hsd17b3 and Insl3) as low as 50 mg/kg. Further study indicated that TCBPA induced reactive oxygen species and caused endoplasmic reticulum stress. In vitro study in TM3 mouse Leydig cells showed that TCBPA indeed induced reactive oxygen species and caused endoplasmic reticulum stress at 75 μM and inhibited testosterone production at this concentration and addition of antioxidant tocopherol can reverse it. These discoveries provide new insights and references for a deeper understanding of the toxic mechanisms of TCBPA on Leydig cells during puberty.
Topics: Rats; Humans; Male; Mice; Animals; Adult; Leydig Cells; Reactive Oxygen Species; Rats, Sprague-Dawley; Sexual Maturation; Semen; Testis; Testosterone; Chlorophenols
PubMed: 38159341
DOI: 10.1016/j.ecoenv.2023.115895 -
General and Comparative Endocrinology Mar 2024Atlantic salmon (Salmo salar) broodstock recruits are normally fed a specialized diet with a higher content of essential nutrients for a limited time period prior to...
Effect of prolonged feeding of broodstock diet with increased inclusion of essential n-3 fatty acids on maturing and spawning performance in 3-year-old Atlantic salmon (Salmo salar).
Atlantic salmon (Salmo salar) broodstock recruits are normally fed a specialized diet with a higher content of essential nutrients for a limited time period prior to fasting and transfer to freshwater. Typically, this period lasts for about six months, but may vary among producers. Reduced use of marine ingredients in commercial salmon diets during the last decades has affected the content of essential nutrients, such as n-3 long chained polyunsaturated fatty acids (LC-PUFA), minerals and vitamins. Furthermore, to minimize the risk of losses and implement new breeding achievements faster, breeding companies have shortened the production cycle of broodstock from 4 to 3 years, which may affect the number of fish that are large enough to mature. In the present study, we have extended the broodstock feeding period from 6 to 15 months prior to the freshwater transfer giving a higher content of n-3 LC-PUFA (higher inclusion of marine oils) from February to December (Phase 1), and thereafter a diet with a higher energy content to ensure growth towards the spring and maturation (Phase 2). Four sea cages with approximately 80.000 salmon postsmolt, two sea cages with males and two with females, were given a control diet and an experimental diet. Samples were taken in Phase 1 at start (1.7 kg), mid (3.4 kg) and end Phase 1/start of Phase 2 (8.3 kg), and end of Phase 2 (13.4 kg). The fish were thereafter fasted, and selected fish transferred to landbased freshwater tanks where light and temperature were used to manipulate the spawning time of the fish in two groups (early or late). Due to disease in the facility, measures of egg quality and hatching were only obtained from the early group. During the trial and spawning period, biometrical measurements were recorded, and samples of liver, gonad, fillet and red blood cells (RBC) were collected for fatty acid composition and blood plasma for analysis of lipid and health-related parameters. Samples were also collected for gonadal transcriptomic analysis by microarray and qPCR (end Phase 2) and plasma steroids (end Phase 2, mid maturation and spawning). Males fed the test diet had a larger body size compared to the control group at the end of Phase 2, while no differences were observed between dietary groups for the females. Total mortality in the trial was lower in the test group compared to the control, losses were caused mainly by sea lice treatments, loser fish or cardiomyopathy syndrome (CMS). The dietary LC-PUFA levels in the test diet were reflected in the tissues particularly during Phase 1, but only different in the fillet samples and eggs at the end of Phase 2 and at spawning. Plasma sex steroids content increased at mid maturation and showed lower levels of androgens and estrogens in females fed the test diet compared to the control. At the end of Phase 2, transcriptional analysis showed upregulation of steroidogenic enzymes, although not reflected in changes in plasma steroids in Phase 2, indicating changes to come during maturation. The differences in LC-PUFA content in tissues and plasma steroids did not appear to affect fecundity, sperm quality, egg survival or hatching rate, but the test group had larger eggs compared to the control in the early spawner-group. Prolonged feeding of n-3 LC-PUFA to pre-puberty Atlantic salmon broodstock appears to be important for higher survival in challenging sea cage environments and has an effect on sex steroid production that, together with high energy diet during early maturation, cause the test group to produce larger eggs.
Topics: Animals; Female; Male; Salmo salar; Sexual Maturation; Semen; Fatty Acids, Omega-3; Fatty Acids; Diet; Steroids; Animal Feed
PubMed: 38142842
DOI: 10.1016/j.ygcen.2023.114434 -
Journal of Dairy Science Jun 2024Reproductive performance is a key determinant of cow longevity in a pasture-based, seasonal dairy system. Unfortunately, direct fertility phenotypes such as intercalving...
Reproductive performance is a key determinant of cow longevity in a pasture-based, seasonal dairy system. Unfortunately, direct fertility phenotypes such as intercalving interval or pregnancy rate tend to have low heritabilities and occur relatively late in an animal's life. In contrast, age at puberty (AGEP) is a moderately heritable, early-in-life trait that may be estimated using an animal's age at first measured elevation in blood plasma progesterone (AGEP4) concentrations. Understanding the genetic architecture of AGEP4 in addition to genetic relationships between AGEP4 and fertility traits in lactating cows is important, as is its relationship with body size in the growing animal. Thus, the objectives of this research were 3-fold. First, to estimate the genetic and phenotypic (co)variances between AGEP4 and subsequent fertility during first and second lactations. Second, to quantify the associations between AGEP4 and height, length, and BW measured when animals were approximately 11 mo old (standard deviation = 0.5). Third, to identify genomic regions that are likely to be associated with variation in AGEP4. We measured AGEP4, height, length, and BW in approximately 5,000 Holstein-Friesian or Holstein-Friesian × Jersey crossbred yearling heifers across 54 pasture-based herds managed in seasonal calving farm systems. We also obtained calving rate (CR42, success or failure to calve within the first 42 d of the seasonal calving period), breeding rate (PB21, success or failure to be presented for breeding within the first 21 d of the seasonal breeding period) and pregnancy rate (PR42, success or failure to become pregnant within the first 42 d of the seasonal breeding period) phenotypes from their first and second lactations. The animals were genotyped using the Weatherby's Versa 50K SNP array (Illumina, San Diego, CA). The estimated heritabilities of AGEP4, height, length, and BW were 0.34 (90% credibility interval [CRI]: 0.30, 0.37), 0.28 (90% CRI: 0.25, 0.31), 0.21 (90% CRI: 0.18, 0.23), and 0.33 (90% CRI: 0.30, 0.36), respectively. In contrast, the heritabilities of CR42, PB21 and PR42 were all <0.05 in both first and second lactations. The genetic correlations between AGEP4 and these fertility traits were generally moderate, ranging from 0.11 to 0.60, whereas genetic correlations between AGEP4 and yearling body-conformation traits ranged from 0.02 to 0.28. Our GWAS highlighted a genomic window on chromosome 5 that was strongly associated with variation in AGEP4. We also identified 4 regions, located on chromosomes 14, 6, 1, and 11 (in order of decreasing importance), that exhibited suggestive associations with AGEP4. Our results show that AGEP4 is a reasonable predictor of estimated breeding values for fertility traits in lactating cows. Although the GWAS provided insights into genetic mechanisms underpinning AGEP4, further work is required to test genomic predictions of fertility that use this information.
Topics: Animals; Cattle; Fertility; Female; Lactation; Genome-Wide Association Study; Phenotype; Sexual Maturation; Pregnancy; Genotype
PubMed: 38135043
DOI: 10.3168/jds.2023-23963 -
PloS One 2023Platynereis dumerilii, a marine annelid, is a model animal that has gained popularity in various fields such as developmental biology, biological rhythms, nervous system...
Platynereis dumerilii, a marine annelid, is a model animal that has gained popularity in various fields such as developmental biology, biological rhythms, nervous system organization and physiology, behaviour, reproductive biology, and epigenetic regulation. The transparency of P. dumerilii tissues at all developmental stages makes it easy to perform live microscopic imaging of all cell types. In addition, the slow-evolving genome of P. dumerilii and its phylogenetic position as a representative of the vast branch of Lophotrochozoans add to its evolutionary significance. Although P. dumerilii is amenable to transgenesis and CRISPR-Cas9 knockouts, its relatively long and indefinite life cycle, as well as its semelparous reproduction have been hindrances to its adoption as a reverse genetics model. To overcome this limitation, an adapted culturing method has been developed allowing much faster life cycling, with median reproductive age at 13-14 weeks instead of 25-35 weeks using the traditional protocol. A low worm density in boxes and a strictly controlled feeding regime are important factors for the rapid growth and health of the worms. This culture method has several advantages, such as being much more compact, not requiring air bubbling or an artificial moonlight regime for synchronized sexual maturation and necessitating only limited water change. A full protocol for worm care and handling is provided.
Topics: Animals; Phylogeny; Epigenesis, Genetic; Annelida; Polychaeta; Life Cycle Stages
PubMed: 38127889
DOI: 10.1371/journal.pone.0295290 -
The Journal of Adolescent Health :... Apr 2024To describe the duration, timing, tempo, and synchronicity of puberty, as well as the correlation between timing and tempo of puberty.
PURPOSE
To describe the duration, timing, tempo, and synchronicity of puberty, as well as the correlation between timing and tempo of puberty.
METHODS
Overall, 15,819 of 22,439 invited children participated in the Puberty Cohort within the Danish National Birth Cohort. Participants completed a web-based questionnaire every 6 months through maturation with questions on current pubertal status. Girls reported current Tanner stage of breast and pubic hair development, and timing of menarche. Boys reported current Tanner stage of genital and pubic hair development, timing of first ejaculation, and vocal changes. While accounting for this interval-censored puberty information, we estimated the duration of puberty. Then, we used a nonlinear mixed effect growth model to estimate timing, tempo, synchronicity of puberty, and correlation between timing and tempo of puberty.
RESULTS
In girls, the average duration of breast development was longer, whereas the average tempo was slower than pubic hair development. The average timing of breast development was earlier than the average timing of pubic hair development. The majority of girls had asynchronous puberty. In boys, the average duration was longer and average tempo slower for genital than pubic hair development. The average timing of genital and pubic hair development were comparable; hence, the majority had synchronous pubertal development. Adolescents who had earlier timing also tended to have a faster tempo.
DISCUSSION
Being one of the largest puberty cohorts worldwide, these unique contemporary data can help physicians, parents, and children to understand and anticipate expected progression through pubertal development.
Topics: Male; Child; Female; Humans; Adolescent; Sexual Maturation; Puberty; Menarche; Breast; Denmark
PubMed: 38127018
DOI: 10.1016/j.jadohealth.2023.10.005 -
BioRxiv : the Preprint Server For... Dec 2023Germ cells are regulated by local microenvironments (niches), which secrete instructive cues. Conserved developmental signaling molecules act as niche-derived regulatory...
Germ cells are regulated by local microenvironments (niches), which secrete instructive cues. Conserved developmental signaling molecules act as niche-derived regulatory factors, yet other types of niche signals remain to be identified. Single-cell RNA-sequencing of sexual planarians revealed niche cells expressing a non-ribosomal peptide synthetase (). Inhibiting led to loss of female reproductive organs and testis hyperplasia. Mass spectrometry detected the dipeptide β-alanyl-tryptamine (BATT), which is associated with reproductive system development and requires and a monoamine-transmitter-synthetic enzyme (AADC) for its production. Exogenous BATT rescued the reproductive defects after or inhibition, restoring fertility. Thus, a non-ribosomal, monoamine-derived peptide provided by niche cells acts as a critical signal to trigger planarian reproductive development. These findings reveal an unexpected function for monoamines in niche-germ cell signaling. Furthermore, given the recently reported role for BATT as a male-derived factor required for reproductive maturation of female schistosomes, these results have important implications for the evolution of parasitic flatworms and suggest a potential role for non-ribosomal peptides as signaling molecules in other organisms.
PubMed: 38106172
DOI: 10.1101/2023.12.06.570471 -
Biochemistry. Biokhimiia Nov 2023Relationships of growth, metabolism, reproduction, and body size to the biological process of aging and longevity have been studied for decades and various unifying... (Review)
Review
Relationships of growth, metabolism, reproduction, and body size to the biological process of aging and longevity have been studied for decades and various unifying "theories of aging" have been proposed to account for the observed associations. In general, fast development, early sexual maturation leading to early reproductive effort, as well as production of many offspring, have been linked to shorter lifespans. The relationship of adult body size to longevity includes a remarkable contrast between the positive correlation in comparisons between different species and the negative correlation seen in comparisons of individuals within the same species. We now propose that longevity and presumably also the rate of aging are related to the "pace-of-life." A slow pace-of-life including slow growth, late sexual maturation, and a small number of offspring, predicts slow aging and long life. The fast pace of life (rapid growth, early sexual maturation, and major reproductive effort) is associated with faster aging and shorter life, presumably due to underlying trade-offs. The proposed relationships between the pace-of-life and longevity apply to both inter- and intra-species comparisons as well as to dietary, genetic, and pharmacological interventions that extend life and to evidence for early life programming of the trajectory of aging. Although available evidence suggests the causality of at least some of these associations, much further work will be needed to verify this interpretation and to identify mechanisms that are responsible.
Topics: Humans; Adult; Longevity; Aging; Reproduction; Biological Phenomena; Body Size
PubMed: 38105191
DOI: 10.1134/S0006297923110020 -
International Journal of Molecular... Nov 2023The castration of stallions is traditionally performed after puberty, at around the age of 2 years old. No studies have focused on the effects of early castration on...
The castration of stallions is traditionally performed after puberty, at around the age of 2 years old. No studies have focused on the effects of early castration on osteoarticular metabolism. Thus, we aimed to compare early castration (3 days after birth) with traditional castration (18 months of age) in horses. Testosterone and estradiol levels were monitored from birth to 33 months in both groups. We quantified the levels of biomarkers of cartilage and bone anabolism (CPII and N-MID) and catabolism (CTX-I and CTX-II), as well as of osteoarthritis (HA and COMP) and inflammation (IL-6 and PGE). We observed a lack of parallelism between testosterone and estradiol synthesis after birth and during puberty in both groups. The extra-gonadal synthesis of steroids was observed around the 28-month mark, regardless of the castration age. We found the expression of estrogen receptor (ESR1) in cartilage and bone, whereas androgen receptor (AR) expression appeared to be restricted to bone. Nevertheless, with respect to osteoarticular metabolism, steroid hormone deprivation resulting from early castration had no discernable impact on the levels of biomarkers related to bone and cartilage metabolism, nor on those associated with OA and inflammation. Consequently, our research demonstrated that early castration does not disrupt bone and cartilage homeostasis.
Topics: Animals; Male; Horses; Sexual Maturation; Orchiectomy; Castration; Testosterone; Estradiol; Osteoarthritis; Inflammation; Biomarkers
PubMed: 38069100
DOI: 10.3390/ijms242316778