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result(s) for
"Masculinization"
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The External Genitalia Score (EGS): A European Multicenter Validation Study
by
Ahmed, S Faisal
,
Desloovere, An
,
Busch, Alexander Siegfried
in
Anogenital
,
Decision making
,
Females
2020
Abstract
Context
Standardized description of external genitalia is needed in the assessment of children with atypical genitalia.
Objectives
To validate the External Genitalia Score (EGS), to present reference values for preterm and term babies up to 24 months and correlate obtained scores with anogenital distances (AGDs).
Design, Setting
A European multicenter (n = 8) validation study was conducted from July 2016 to July 2018.
Patients and Methods
EGS is based on the external masculinization score but uses a gradual scale from female to male (range, 0–12) and terminology appropriate for both sexes. The reliability of EGS and AGDs was determined by the interclass correlation coefficient (ICC). Cross-sectional data were obtained in 686 term babies (0–24 months) and 181 preterm babies, and 111 babies with atypical genitalia.
Results
The ICC of EGS in typical and atypical genitalia is excellent and good, respectively. Median EGS (10th to 90th centile) in males < 28 weeks gestation is 10 (8.6–11.5); in males 28–32 weeks 11.5 (9.2–12); in males 33–36 weeks 11.5 (10.5–12) and in full-term males 12 (10.5–12). In all female babies, EGS is 0 (0-0). The mean (SD) lower/upper AGD ratio (AGDl/u) is 0.45 (0.1), with significant difference between AGDl/u in males 0.49 (0.1) and females 0.39 (0.1) and intermediate values in differences of sex development (DSDs) 0.43 (0.1). The AGDl/u correlates with EGS in males with typical genitalia and in atypical genitalia.
Conclusions
EGS is a reliable and valid tool to describe external genitalia in premature and term babies up to 24 months. EGS correlates with AGDl/u in males. It facilitates standardized assessment, clinical decision-making and multicenter research.
Journal Article
Effect of natural and synthetic androgen hormone on sex reversal of Nile Tilapia (Oreochromis niloticus)
2024
Abstract The present study aimed to produce a monosex population of all male Nile tilapia (Oreochromis spp.) using 17α-methyl testosterone and common carp testes (as a source of natural androgen). Trial was conducted into two consecutive phases, the first was fry (4-5 days old)administration with negative control (without hormone) and positive control (with hormone) feed viz., MT1:60mg/kg, MT2:70mg/kg (17α-MT), carp testis CT1:70% and CT2:80% for 30 days to reverse the sex of male fish and the second phase was nursing the fingerlings for two months on control diet (32% Crude protein).Results revealed a significant growth rate (P<0.05) in the control group where final weight (4.8±0.34ab) and weight gained was recorded as 0.66±0.03ac. In proximate chemical composition of body meat, CT2 treatment showed maximum retention of crude protein, crude fat, and ash whereas dry matter showed maximum retention in MT2 and CT1 treatments. Morphological and histological examination revealed significant difference (p<0.05) in phenotypic males of Nile tilapia fed with the highest percent in MT-treated diet (MT2) of 95±0.58a while MT1, CT2 and CT1 had males of 85±6.0b, 70±5.0b and 65±6.5b, respectively. It was concluded that synthetic androgen (17αMT) was more effective for masculinization but natural androgen scan be an alternative method to produce male tilapia population in an environment-friendly manner as they are inexpensive, eco-friendly, and radially available. These results suggested that synthetic and natural androgen supplementation in the diet plays a significant role in improving growth performance and body composition. Resumo O presente estudo teve como objetivo produzir uma população monossexuada de todos os machos de tilápia do Nilo (Oreochromis spp.) usando 17α-metil testosterona e testículos de carpa comum como fonte de andrógeno natural. O ensaio foi conduzido em duas fases consecutivas, a primeira foi a administração de alevinos (4-5 dias) com controle negativo (sem hormônio) e controle positivo (com hormônio), viz., MT1:60mg/kg, MT2:70mg/kg (17α -MT), testículos de carpa CT1:70% e CT2:80% por 30 dias para inverter o sexo dos peixes machos e a segunda fase foi amamentar os alevinos por dois meses com dieta controle (32% de proteína bruta), e analisar a taxa de crescimento (p < 0,05) no grupo controle, em que o peso final (4,8 ± 0,34 ab) e o peso ganho foram registrados como 0,66 ± 0,03 ac. Na composição química aproximada da carne corporal, o tratamento CT2 mostrou retenção máxima de proteína bruta, gordura bruta e cinzas, enquanto a matéria seca apresentou retenção máxima nos tratamentos MT2 e CT1. O exame morfológico e histológico revelou diferença significativa (p < 0,05) nos machos fenotípicos de tilápia do Nilo alimentados com o maior percentual na dieta tratada com MT (MT2) de 95 ± 0,58a enquanto MT1, CT2 e CT1 tiveram machos de 85 ± 6,0b, 70 ± 5,0 e 65 ± 6,5b, respectivamente. Concluiu-se que o andrógeno sintético (17αMT) foi mais eficaz para a masculinização, entretanto os andrógenos naturais podem ser um método alternativo para produzir população de tilápias machos de maneira ecológica, pois são baratos, ecológicos e estão disponíveis radialmente. Esses resultados sugerem que a suplementação de andrógenos sintéticos e naturais na dieta desempenha um papel significativo na melhoria do desempenho do crescimento e da composição corporal.
Journal Article
Heat-induced masculinization in domesticated zebrafish is family-specific and yields a set of different gonadal transcriptomes
by
Piferrer, Francesc
,
Liew, Woei Chang
,
Sreenivasan, Rajini
in
Biological Sciences
,
Chemical pollution
,
Climate change
2017
Understanding environmental influences on sex ratios is important for the study of the evolution of sex-determining mechanisms and for evaluating the effects of global warming and chemical pollution. Fishes exhibit sexual plasticity, but the underlying mechanisms of environmental effects on their reproduction are unclear even in the well-established teleost research model, the zebrafish. Here we established the conditions to study the effects of elevated temperature on zebrafish sex. We showed that sex ratio response to elevated temperature is family-specific and typically leads to masculinization (female-to-male sex reversal), resulting in neomales. These results uncovered genotype-by-environment interactions that support a polygenic sex determination system in domesticated (laboratory) zebrafish. We found that some heat-treated fish had gene expression profiles similar to untreated controls of the same sex, indicating that they were resistant to thermal effects. Further, most neomales had gonadal transcriptomes similar to that of regular males. Strikingly, we discovered heat-treated females that displayed a normal ovarian phenotype but with a “male-like” gonadal transcriptome. Such major transcriptomic reprogramming with preserved organ structure has never been reported. Juveniles were also found to have a male-like transcriptome shortly after exposure to heat. These findings were validated by analyzing the expression of genes and signaling pathways associated with sex differentiation. Our results revealed a lasting thermal effect on zebrafish gonads, suggesting new avenues for detection of functional consequences of elevated temperature in natural fish populations in a global warming scenario.
Journal Article
Activation of stress response axis as a key process in environment-induced sex plasticity in fish
by
Castañeda-Cortés, D. C.
,
Strobl-Mazzulla, P. H.
,
Hattori, R. S.
in
Acidity
,
Animals
,
Biochemistry
2020
The determination of sex is an important hallmark in the life cycle of organisms, in which the fate of gonads and then the individual sex are defined. In gonochoristic teleost fish, this process is characterized by a high plasticity, considering that in spite of genotypic sex many environmental factors can cause shifts from one to another molecular pathway, resulting in organisms with mismatching genotypic and phenotypic sexes. Interestingly, in most instances, both female-to-male or male-to-female sex-reversed individuals develop functional gonads with normal gametogenesis and respective progenies with full viability. The study of these mechanisms is being spread to other non-model species or to those inhabiting more extreme environmental conditions. Although water temperature is an important mechanism involved in sex determination, there are other environmental stressors affected by the climate change which are also implicated in stress response-induced masculinization in fish. In this regard, the brain has emerged as the transducer of the environment input that can influence the gonadal fate. Furthermore, the evaluation of other environmental stressors or their synergic effect on sex determination at conditions that simulate the natural environments is growing gradually. Within such scope, the concerns related to climate change impacts rely on the fact that many of biotic and abiotic parameters reported to affect sex ratios are expected to increase concomitantly as a result of increased greenhouse gas emissions and, particularly worrying, many of them are related to male bias in the populations, such as high temperature, hypoxia, and acidity. These environmental changes can also generate epigenetic changes in sex-related genes affecting their expression, with implications on sex differentiation not only of exposed individuals but also in following generations. The co-analysis of multi-stressors with potential inter- and transgenerational effects is essential to allow researchers to perform long-term predictions on climate change impacts in wild populations and for establishing highly accurate monitoring tools and suitable mitigation strategies.
Journal Article
Extensive reproductive disruption, ovarian masculinization and aromatase suppression in Atlantic croaker in the northern Gulf of Mexico hypoxic zone
2012
The long-term impacts on marine ecosystems of the recent dramatic worldwide increase in the incidence of coastal hypoxia are unknown. Here, we show widespread reproductive disruption in Atlantic croakers collected from hypoxic sites approximately 120 km apart in the extensive northern Gulf of Mexico continental shelf hypoxic zone. Gonadal growth and gamete production were impaired in croakers from hypoxic sites compared with fish from reference normoxic sites east of the Mississippi River Delta. Male germ cells were detected in approximately 19 per cent of croaker ovaries collected in the hypoxic region, but were absent in ovaries from normoxic sites. In addition, the sex ratio was skewed towards males at the hypoxic sites. The masculinization and other reproductive disruptions were associated with declines in neuroendocrine function, as well as ovarian and brain expression of aromatase (the enzyme that converts androgens to oestrogens). A similar incidence of ovarian masculinization and decline in ovarian aromatase expression were observed in croaker after chronic laboratory hypoxia exposure, indicating that ovarian masculinization is a specific hypoxia response and is due to decreased aromatase activity. The results suggest severe reproductive impairment can occur over large coastal regions in marine fish populations exposed to seasonal hypoxia, with potential long-term impacts on population abundance.
Journal Article
Masculinized females produce heavier offspring in a group living rodent
by
Ramírez-Estrada, Juan
,
Soto-Gamboa, Mauricio
,
Sepúlveda, Roger D.
in
Animal reproduction
,
Animals
,
Body Weight
2016
1. Alternative morphotypes have been reported less frequently in females than in males. An exception to this rule is the gradient of phenotypical masculinization reported in some female mammals, in which feminized and masculinized females represent two opposite ends along this gradient. These phenotypical differences originate during prenatal development as the consequence of maternal effects. Feminized and masculinized females differ in several traits, including morphological, physiological, behavioural and reproductive traits. 2. Differences previously reported in reproductive traits between feminized and masculinized females come mostly from mechanistic studies performed in the laboratory, and not necessarily on social species. As a result, it is unclear to what extent these reported differences between female alternative morphotypes materialize in wild, natural populations. 3. We quantified the effect of female alternative morphotype on female reproductive traits in a natural population of Octodon degus, a highly social rodent. We assessed female alternative morphotype through a continuous gradient of anogenital distance. Thus, feminized females were close to the short end of anogenital distance, while masculinized females were close to the long end of this gradient. We also tested the hypothesis that the social environment interacts with female morphotype to influence female reproductive traits. 4. In female degus, only body weight affected litter size, where heavier females weaned more offspring. Masculinized females delivered male-biased litters and weaned heavier offspring. Lastly, masculinized females gave birth later in the breeding season compared to feminized females. 5. Contrary to previous claims, our findings do not support that masculinized females are less fertile than feminized females. Moreover, masculinized females produced heavier, potentially higher quality offspring compared with feminized females.
Journal Article
A new view of sexual differentiation of mammalian brain
2020
Establishment of enduring sex differences in brain and behavior occurs during pre- or perinatal development, depending on species. For over 50 years the focus has been on gonadal steroid production by male fetuses and the impact on developing brain. An increasing awareness of the importance of sex chromosome complement has broadened the focus but identifying specific roles in development has yet to be achieved. Recent emphasis on transcriptomics has revealed myriad and unexpected differences in gene expression in specific regions of male and female brains which may produce sex differences, serve a compensatory role or provide latent sex differences revealed only in response to challenge. More surprising, however, has been the consistent observation of a central role for inflammatory signaling molecules and immune cells in masculinization of brain and behavior. The signal transduction pathways and specific immune cells vary by brain region, as does the neuroanatomical substrate subject to differentiation, reflecting substantial complexity emerging from what may be a common origin, the maternal immune system. A working hypothesis integrating these various ideas is proposed.
Journal Article
Comparative RNA-Seq analysis reveals genes associated with masculinization in female Cannabis sativa
by
Holbrook, Larry
,
Mahmoud, Soheil S.
,
Adal, Ayelign M.
in
Agriculture
,
Biomedical and Life Sciences
,
Biotechnology
2021
Genetically female Cannabis sativa plants normally bear female flowers, but can develop male flowers in response to environmental and developmental cues. In an attempt to elucidate the molecular elements responsible for sex expression in C. sativa plants, we developed genetically female lines producing both female and chemically-induced male flowers. Furthermore, we carried out RNA-Seq assays aimed at identifying differentially expressed genes responsible for male flower development in female plants. The results revealed over 10,500 differentially expressed genes, of which around 200 potentially control masculinization of female cannabis plants. These genes include transcription factors and other genes involved in male organ (i.e., anther and pollen) development, as well as genes involved in phytohormone signalling and male-biased phenotypes. The expressions of 15 of these genes were further validated by qPCR assay confirming similar expression patterns to that of RNA-Seq data. These genes would be useful for understanding predisposed plants producing flowers of both sex types in the same plant, and help breeders to regulate the masculinization of female plants through targeted breeding and plant biotechnology.
Journal Article
Transmasculine individuals’ experiences with lactation, chestfeeding, and gender identity: a qualitative study
by
Walks, Michelle
,
MacDonald, Trevor
,
West, Diana
in
Adult
,
Babies
,
Breast Feeding - psychology
2016
Background
Transmasculine individuals are people who were assigned as female at birth, but identify on the male side of the gender spectrum. They might choose to use and engage their bodies to be pregnant, birth a baby, and chestfeed. This study asked an open research question, “What are the experiences of transmasculine individuals with pregnancy, birthing, and feeding their newborns?”
Methods
Participants who self-identified as transmasculine and had experienced or were experiencing pregnancy, birth, and infant feeding were recruited through the internet and interviewed. Interviews were transcribed verbatim. We used interpretive description methodology to analyze the data. Our analysis was guided by our awareness of concepts and history important to the transgender community.
Results
Out of 22 participants, 16 chose to chestfeed for some period of time, four participants did not attempt chestfeeding, and two had not reached the point of infant feeding (i.e., were still pregnant or had a miscarriage). Nine of the 22 study participants had chest masculinization surgery before conceiving their babies. Six participants had the surgery after their children were born, five desired the surgery in the future, and two did not want it at all.
Chest care, lactation, and chestfeeding in the context of being a transgender person are reported in this paper. The participants’ experiences of gender dysphoria, chest masculinization surgery before pregnancy or after weaning, accessing lactation care as a transmasculine person, and the question of restarting testosterone emerged as data. We present the participants’ experiences in a chronological pattern with the categories of before pregnancy, pregnancy, postpartum (6 weeks post birth), and later stage (beyond 6 weeks).
Conclusions
The majority of participants chose to chestfeed while some did not due to physical or mental health reasons. Care providers should communicate an understanding of gender dysphoria and transgender identities in order to build patient trust and provide competent care. Further, health care providers need to be knowledgeable about lactation and chest care following chest masculinization surgery and during binding, regardless of the chosen feeding method and through all stages: before pregnancy, during pregnancy, postpartum, and afterward.
Journal Article
Improvement of Testicular Steroidogenesis Using Flavonoids and Isoflavonoids for Prevention of Late-Onset Male Hypogonadism
2020
Androgen production, being important for male fertility, is mainly accomplished by the Leydig cells from the interstitial compartment of the testis. Testosterone plays a critical role in testis development, normal masculinization, and the maintenance of spermatogenesis. Within seminiferous tubules, appropriate Sertoli cell function is highly dependent on testicular androgen levels and is essential to initiate and maintain spermatogenesis. During aging, testosterone production by the testicular Leydig cells declines from the 30s in humans at a rate of 1% per year. This review outlines the recent findings regarding the use of flavonoids and isoflavonoids to improve testosterone production, contributing to normal spermatogenesis and preventing age-related degenerative diseases associated with testosterone deficiency. With the cumulation of information on the actions of different flavonoids and isoflavonoids on steroidogenesis in Leydig cells, we can now draw conclusions regarding the structure-activity relationship on androgen production. Indeed, flavonoids having a 5,7-dihydroxychromen-4-one backbone tend to increase the expression of the steroidogenic acute regulatory protein (StAR), being critical for the entry of cholesterol into the mitochondria, leading to increased testosterone production from testis Leydig cells. Therefore, flavonoids and isoflavonoids such as chrysin, apigenin, luteolin, quercetin, and daidzein may be effective in delaying the initiation of late-onset hypogonadism associated with aging in males.
Journal Article