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Indian Journal of Pediatrics Oct 2023Enlargement of breasts among boys is termed gynecomastia. This could be due to an alteration in the androgen-estrogen ratio along with the effects of other hormones... (Review)
Review
Enlargement of breasts among boys is termed gynecomastia. This could be due to an alteration in the androgen-estrogen ratio along with the effects of other hormones including growth hormone, insulin like growth factor 1, prolactin, and other factors affecting aromatase enzyme. The common causes of gynecomastia are pubertal gynecomastia, obesity, drugs and hypogonadism. Several other diseases including liver or renal failure, thyrotoxicosis, Klinefelter syndrome, tumors and environmental pollutants can cause gynecomastia. History and clinical examination will help formulate targeted investigations and management. The factors to be evaluated in these include examination of breasts and testes, in addition to other parts of systemic examination. Treatment of underlying disorders can improve gynecomastia, such as use of testosterone in hypogonadism. Some boys may not need any intervention as gynecomastia may resolve on its own. Medical management is useful in simple gynecomastia. Tamoxifen has been tried successfully in adolescents with gynecomastia. Other drugs including clomiphene, danazol, letrozole and anastrozole have not been consistently useful in this age group. In severe chronic gynecomastia, surgery is the treatment of choice.
Topics: Adolescent; Male; Humans; Gynecomastia; Hypertrophy; Tamoxifen; Growth Hormone; Hypogonadism
PubMed: 37592101
DOI: 10.1007/s12098-023-04810-7 -
Metabolism: Clinical and Experimental Sep 2018Reproduction is controlled by the hypothalamic-pituitary-gonadal (HPG) axis. Gonadotropin-releasing hormone (GnRH) neurons play a central role in this axis through... (Review)
Review
Reproduction is controlled by the hypothalamic-pituitary-gonadal (HPG) axis. Gonadotropin-releasing hormone (GnRH) neurons play a central role in this axis through production of GnRH, which binds to a membrane receptor on pituitary gonadotrophs and stimulates the biosynthesis and secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Multiple factors affect GnRH neuron migration, GnRH gene expression, GnRH pulse generator, GnRH secretion, GnRH receptor expression, and gonadotropin synthesis and release. Among them anosmin is involved in the guidance of the GnRH neuron migration, and a loss-of-function mutation in its gene leads to a failure of their migration from the olfactory placode to the hypothalamus, with consequent anosmic hypogonadotropic hypogonadism (Kallmann syndrome). There are also cases of hypogonadotropic hypogonadim with normal sense of smell, due to mutations of other genes. Another protein, kisspeptin plays a crucial role in the regulation of GnRH pulse generator and the pubertal development. GnRH is the main hypothalamic regulator of the release of gonadotropins. Finally, FSH and LH are the essential hormonal regulators of testicular functions, acting through their receptors in Sertoli and Leydig cells, respectively. The main features of the male HPG axis will be described in this review.
Topics: Animals; Gonadotropin-Releasing Hormone; Gonadotropins; Gonads; Humans; Hypothalamo-Hypophyseal System; Male; Mice; Reproduction
PubMed: 29223677
DOI: 10.1016/j.metabol.2017.11.018 -
Endocrine Reviews Sep 2022Delayed puberty (DP) defines a retardation of onset/progression of sexual maturation beyond the expected age from either a lack/delay of the... (Review)
Review
Delayed puberty (DP) defines a retardation of onset/progression of sexual maturation beyond the expected age from either a lack/delay of the hypothalamo-pituitary-gonadal axis activation or a gonadal failure. DP usually gives rise to concern and uncertainty in patients and their families, potentially affecting their immediate psychosocial well-being and also creating longer term psychosexual sequelae. The most frequent form of DP in younger teenagers is self-limiting and may not need any intervention. Conversely, DP from hypogonadism requires prompt and specific treatment that we summarize in this review. Hormone therapy primarily targets genital maturation, development of secondary sexual characteristics, and the achievement of target height in line with genetic potential, but other key standards of care include body composition and bone mass. Finally, pubertal induction should promote psychosexual development and mitigate both short- and long-term impairments comprising low self-esteem, social withdrawal, depression, and psychosexual difficulties. Different therapeutic options for pubertal induction have been described for both males and females, but we lack the necessary larger randomized trials to define the best approaches for both sexes. We provide an in-depth and updated literature review regarding therapeutic options for inducing puberty in males and females, particularly focusing on recent therapeutic refinements that better encompass the heterogeneity of this population, and underlining key differences in therapeutic timing and goals. We also highlight persistent shortcomings in clinical practice, wherein strategies directed at "the child with delayed puberty of uncertain etiology" risk being misapplied to older adolescents likely to have permanent hypogonadism.
Topics: Adolescent; Child; Female; Gonadotropins; Humans; Hypogonadism; Male; Puberty; Puberty, Delayed; Testosterone
PubMed: 34864951
DOI: 10.1210/endrev/bnab043 -
The Angle Orthodontist Mar 2021To evaluate whether the success of miniscrew-assisted rapid palatal expansion (MARPE), performed in patients with advanced bone maturation is related to factors such as...
OBJECTIVES
To evaluate whether the success of miniscrew-assisted rapid palatal expansion (MARPE), performed in patients with advanced bone maturation is related to factors such as midpalatal suture (MPS) maturation, age, sex, or bicortical mini-implant anchorage.
MATERIALS AND METHODS
Twenty-eight cone beam computed tomography (CBCT) scans of adults and post-pubertal adolescents treated by MARPE were included in the sample. CBCT images before (T0) and after expansion (T1) were used to evaluate the skeletal changes and the success or failure of MARPE. Axial images of MPS were extracted from T0 and classified into one of the five maturation stages. The correlation between MARPE success and the factors of age, sex, MPS maturation, and bicortical mini-implant anchorage was investigated.
RESULTS
Only the age showed a statistically significant negative correlation with MARPE success and all the skeletal measures. There was an 83.3% success rate among individuals aged 15 to 19 years, 81.8% from 20 to 29 years, and 20% from 30 to 37 years. MPS maturation showed a negative correlation with the expansion effect. Subjects with stages B or C of MPS maturation showed a 100% success rate, followed by stage D (62.5%) and stage E (58.3%).
CONCLUSIONS
As age increased, there was a decrease in MARPE success and the skeletal effects of maxillary expansion. Sex and bicortical mini-implant anchorage were not shown to be relevant factors. There was no correlation between MPS maturation and MARPE success; however, it was observed that all cases of MARPE failure were classified as stage D or E of MPS maturation.
Topics: Adolescent; Adult; Cone-Beam Computed Tomography; Cranial Sutures; Humans; Maxilla; Palatal Expansion Technique; Palate; Young Adult
PubMed: 33351888
DOI: 10.2319/051420-436.1 -
Best Practice & Research. Clinical... Jun 2019The term primary gonadal failure encompasses not only testicular insufficiency in 46,XY males and ovarian insufficiency in 46,XX females, but also those disorders of sex... (Review)
Review
The term primary gonadal failure encompasses not only testicular insufficiency in 46,XY males and ovarian insufficiency in 46,XX females, but also those disorders of sex development (DSD) which result in gender assignment that is at variance with the genotype and gonadal type. In boys, causes of gonadal failure include Klinefelter and other aneuploidy syndromes, bilateral cryptorchidism, testicular torsion, and forms of 46,XY DSD such as partial androgen insensitivity. Causes in girls include Turner syndrome and other aneuploidies, galactosemia, and autoimmune ovarian failure. Iatrogenic causes in both boys and girls include the late effects of childhood cancer treatment, total body irradiation prior to bone marrow transplantation, and iron overload in transfusion-dependent thalassaemia. In this paper, a brief description of the physiology of testicular and ovarian development is followed by a section on the causes and practical management of gonadal impairment in boys and girls. Protocols for pubertal induction and post-pubertal hormone replacement - intramuscular, oral and transdermal testosterone in boys; oral and transdermal oestrogen in girls - are then given. Finally, current and future strategies for assisted conception and fertility preservation are discussed.
Topics: Androgen-Insensitivity Syndrome; Child; Disorders of Sex Development; Female; Fertility Preservation; Humans; Male; Primary Ovarian Insufficiency
PubMed: 31327696
DOI: 10.1016/j.beem.2019.101295 -
Endocrine Reviews Jan 2024Kisspeptin (KP) and neurokinin B (NKB) are neuropeptides that govern the reproductive endocrine axis through regulating hypothalamic gonadotropin-releasing hormone... (Review)
Review
Kisspeptin (KP) and neurokinin B (NKB) are neuropeptides that govern the reproductive endocrine axis through regulating hypothalamic gonadotropin-releasing hormone (GnRH) neuronal activity and pulsatile GnRH secretion. Their critical role in reproductive health was first identified after inactivating variants in genes encoding for KP or NKB signaling were shown to result in congenital hypogonadotropic hypogonadism and a failure of pubertal development. Over the past 2 decades since their discovery, a wealth of evidence from both basic and translational research has laid the foundation for potential therapeutic applications. Beyond KP's function in the hypothalamus, it is also expressed in the placenta, liver, pancreas, adipose tissue, bone, and limbic regions, giving rise to several avenues of research for use in the diagnosis and treatment of pregnancy, metabolic, liver, bone, and behavioral disorders. The role played by NKB in stimulating the hypothalamic thermoregulatory center to mediate menopausal hot flashes has led to the development of medications that antagonize its action as a novel nonsteroidal therapeutic agent for this indication. Furthermore, the ability of NKB antagonism to partially suppress (but not abolish) the reproductive endocrine axis has supported its potential use for the treatment of various reproductive disorders including polycystic ovary syndrome, uterine fibroids, and endometriosis. This review will provide a comprehensive up-to-date overview of the preclinical and clinical data that have paved the way for the development of diagnostic and therapeutic applications of KP and NKB.
Topics: Pregnancy; Female; Humans; Neurokinin B; Kisspeptins; Gonadotropin-Releasing Hormone; Reproduction; Hypothalamus
PubMed: 37467734
DOI: 10.1210/endrev/bnad023 -
European Journal of Cancer (Oxford,... Sep 2022To provide practice guidelines about fertility preservation (FP) in oncology. (Review)
Review
AIM
To provide practice guidelines about fertility preservation (FP) in oncology.
METHODS
We selected 400 articles after a PubMed review of the literature (1987-2019).
RECOMMENDATIONS
Any child, adolescent and adult of reproductive age should be informed about the risk of treatment gonadotoxicity. In women, systematically proposed FP counselling between 15 and 38 years of age in case of treatment including bifunctional alkylating agents, above 6 g/m2 cyclophosphamide equivalent dose (CED), and for radiation doses on the ovaries ≥3 Gy. For postmenarchal patients, oocyte cryopreservation after ovarian stimulation is the first-line FP technique. Ovarian tissue cryopreservation should be discussed as a first-line approach in case of treatment with a high gonadotoxic risk, when chemotherapy has already started and in urgent cases. Ovarian transposition is to be discussed prior to pelvic radiotherapy involving a high risk of premature ovarian failure. For prepubertal girls, ovarian tissue cryopreservation should be proposed in the case of treatment with a high gonadotoxic risk. In pubertal males, sperm cryopreservation must be systematically offered to any male who is to undergo cancer treatment, regardless of toxicity. Testicular tissue cryopreservation must be proposed in males unable to cryopreserve sperm who are to undergo a treatment with intermediate or severe risk of gonadotoxicity. In prepubertal boys, testicular tissue preservation is: - recommended for chemotherapy with a CED ≥7500 mg/m2 or radiotherapy ≥3 Gy on both testicles. - proposed for chemotherapy with a CED ≥5.000 mg/m2 or radiotherapy ≥2 Gy. If several possible strategies, the ultimate choice is made by the patient.
Topics: Cryopreservation; Female; Fertility Preservation; Humans; Male; Neoplasms; Ovary; Semen
PubMed: 35932626
DOI: 10.1016/j.ejca.2022.05.013