Talk:Puberty Development
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Glossary Links
Cite this page: Hill, M.A. (2024, June 14) Embryology Puberty Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Puberty_Development |
2010
Quantification of cranial base growth during pubertal growth
Malta LA, Ortolani CF, Faltin K. J Orthod. 2009 Dec;36(4):229-35. PMID: 19934240
2004
BJU Int. 2004 May;93(7):1015-7. Correlation of ultrasonographic and orchidometer measurements of testis volume in adults. Schiff JD1, Li PS, Goldstein M. Author information Abstract OBJECTIVE: To determine the correlation between testicular volume measured with an orchidometer or high-resolution scrotal ultrasonography (US) with colour-flow Doppler analysis. PATIENTS AND METHODS: In all, 159 men (mean age 36.6 years) presenting for infertility evaluation underwent both a physical examination by a one experienced examiner and high-resolution US with colour-flow Doppler analysis. An orchidometer was also used to measure testicular volume after stretching the scrotal skin tightly over the testis and after warming with a heating pad. The US was interpreted by a radiologist who had no knowledge of the orchidometer estimates. The volume was calculated as 0.71 x length x width x height. RESULTS: For the right testes the mean orchidometer and US estimates were 18.4 and 18.3 mL, yielding a correlation coefficient of 0.72 (r (2) = 0.52, P < 0.01). On the left the respective values were 17.1 and 16.9 mL, with a correlation coefficient of 0.69 (r (2) = 0.48, P < 0.01). CONCLUSION: Orchidometer estimates of testicular volume correlate closely and very significantly with US estimates in adults. In the hands of an experienced examiner orchidometer measurements provide an accurate, rapid and inexpensive assessment of testicular volume. PMID 15142154
Puberty
Can occur over a broad range of time and differently for each sex: girls (age 7 to 13) boys (age 9 to 15).
The physical characteristics that can be generally measured are: genital stage, pubic hair, axillary hair, menarche, breast, voice change and facial hair.
The physiological process is initiated by the hypothalmus releasing gonadotropin releasing hormone (GnRH) which signals the pituitary to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH) which in turn signals throughout the body sexual development.
Links: Endocrinology - Puberty | Endocrinology - Endocrine changes in puberty | Endocrinology - Gonad | Clinical Methods - The Adolescent Patient | Clinical Methods - Staging Criteria for Secondary Sexual Development | NICHD - Puberty | UCSF - Male Development |
Precocious Puberty
Premature development of the signs of puberty which can occur in both girls (before age 7 or 8) and in boys (before age 9).
Links: Endocrinology - Precocious sexual development | NICHD - Precocious Puberty | Nemours Foundation - Precocious Puberty | MedlinePlus - Obesity May Trigger Earlier Puberty for Girls | Time Magazine - Teens Before Their Time |
Delayed Puberty
Determined in boys by a lack of increase in testicular volume by the age of 14 years. In girls, no breast development by the age of 13.5 years and a lack of menstruation by the age of 16 years. There can also be a "pubertal arrest" where there is no progress in puberty over 2 year period.
Links: Endocrinology - Delayed puberty | Endocrinology - Definitions and causes of delayed puberty | Nemours Foundation - Delayed Puberty
Kisspeptin
While the hypothalamic expression of gonadotropin releasing hormone (GnRH) is a known puberty trigger, it was not known what initiated the GnRH secretion. Recent research suggests that an earlier signal could come from increased neuronal and hypothalamic expression of a peptide family (kisspeptins) and their receptor (G protein-coupled receptor GPR54) in the hypothalamus. A single gene (Kiss1) encodes these 145 amino acid kisspeptins and it was originally identified as a human metastasis suppressor gene (suppresses melanomas and breast carcinomas without affecting tumorigenicity).
Two hypothalamic nuclei, the arcuate nucleus and anteroventral periventricular nucleus (AVPV), are thought to contain the kisspeptin secreting neurons.
The anteroventral periventricular nucleus differs in males and females (sexually dimorphic). The arcuate nucleus (and medial preoptic area, MPOA) is linked into the olfactory system, through the vomeronasal organ, perhaps in relation to the influence of pheromones on sexual behavior and neuroendocrine function (in mice).
| File:Chockiss.jpeg | Why Kisspeptin?
The original discovery of the peptide was made by scientists located in Hershey, PA, USA and named the gene "Kiss1" after the "Hershey chocolate kiss". |
References: Seminara SB. Mechanisms of Disease: the first kiss-a crucial role for kisspeptin-1 and its receptor, G-protein-coupled receptor 54, in puberty and reproduction. Nat Clin Pract Endocrinol Metab. 2006 Jun;2(6):328-34. | Dungan HM, Clifton DK, Steiner RA. Minireview: kisspeptin neurons as central processors in the regulation of gonadotropin-releasing hormone secretion. Endocrinology. 2006 Mar;147(3):1154-8.
Links: OMIM - KISS1 METASTASIS SUPPRESSOR | OMIM - G-protein-coupled receptor 54 |
Gonadotropin Releasing Hormone (GnRH)
Neurons in the hypothalamic arcuate nucleus (and other nuclei) synthesise this hormone along with gonadotrophin associated peptide (GAP), which are both released and transported by hypophyseal portal capillaries to the anterior pituitary and bound by a membrane receptor.
GnRH increases during early puberty, followed by an increased pituitary responsiveness, then increasing sex steroid levels and then increased nocternal Luteinizing hormone (LH) secretion.
Links: Endocrinology - GnRH and the control of gonadotrophin synthesis and secretion | Endocrinology - Synthesis of GnRH and its actions on pituitary gonadotrophs |
Australian
HealthInsite Puberty
Child and Youth Health (SA) - Puberty
American
National Institute of Child Health and Human Development Puberty | Precocious Puberty
American Academy of Family Physicians Puberty: What to Expect When Your Child Goes through Puberty
Nemours Foundation Precocious Puberty | Delayed Puberty |
Reading
Most embryology textbooks (by definition) do not cover postnatal developmenty in any detail. The links below are to useful scientific external online resources.
- PHYSICAL DEVELOPMENT, GROWTH, MATURATION, AND AGEING
- Patterns of Human Growth (PDF document)
- Causes and Mechanisms of Linear Growth Retardation
The links below are to general public external text resources (this listing is for information purposes only and is not intended as an endorsement of a commercial product).
- Ready, Set, Grow!: A What's Happening to My Body? Book for Younger Girls, by Lynda Madaras and Linda Davick
- What's Happening to My Body? Book for Boys: The New Growing-Up Guide for Parents and Sons, Third Edition by Lynda Madaras, Area Madaras, Dane Saavedra, and Simon Sullivan
- Sex, Puberty, and All That Stuff: A Guide to Growing Up, by Jacqui Bailey and Jan McCafferty
