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Processing and cryopreservation of testicular sperm
Published in David K. Gardner, Ariel Weissman, Colin M. Howles, Zeev Shoham, Textbook of Assisted Reproductive Techniques, 2017
Amin S. Herati, Mark C. Lindgren, Samuel J. Ohlander, Larry I. Lipshultz
Additional consideration must be given to prepubescent boys who undergo testis biopsy for fertility preservation prior to undergoing chemotherapy or radiation. A sevenyear longitudinal study of the onset of sperm production (spermarche) identified spermarche as an early pubertal event occurring at a median age of 13.4 years (range 11.7–15.3 years) in 40 boys (18). Therefore, it is reasonable to perform a testicular biopsy for sperm extraction in boys over the age of 10 years (19). If no mature spermatozoa are found or the patient is less than 10 years of age, the biopsy sample should be cleansed of erythrocytes, sectioned into 1–4-mm3 fragments, and placed into cryovials containing 5% dimethyl sulfoxide (DMSO) in order to preserve the architecture of the seminiferous tubules and to maintain immature spermatogonial cell-to-cell contact with its adjacent cells (20). Maintaining this cell-to-cell contact is important for post-thaw maturation of spermatogonia cells (21).
Fertility preservation
Published in David M. Luesley, Mark D. Kilby, Obstetrics & Gynaecology, 2016
Men should be offered the opportunity to bank sperm before cancer treatment (Table 92.3). Spermache occurs at a median age of 13.4 (range 11.7–15.3) years. Post-pubertal males will ordinarily be capable of ejaculation and can provide sperm for storage. In males who cannot ejaculate or who are too young, electro-ejaculation, epididymal sperm aspiration or testicular sperm extraction may be performed. Cryopreserved material is usually stored for an initial period of 10 years; however, continued storage of cryopreserved sperm, beyond 10 years, should be offered to men who remain at risk of significant infertility. Testicular tissue cryopreservation from prepubescent males remains experimental.
Serum uric acid and blood pressure among adolescents: data from the Nutrition and Health Survey in Taiwan (NAHSIT) 2010–2011
Published in Blood Pressure, 2021
Kuan-Hung Lin, Fu-Shun Yen, Harn-Shen Chen, Chii-Min Hwu, Chen-Chang Yang
The Nutrition and Health Survey in Taiwan Junior and Senior High School Adolescents (NAHSIT Adolescents 2010–2011) is a nationwide epidemiological survey that focussed on the nutrition and the health status of adolescents in Taiwan. After applying a stratified, multistage, and clustered sampling method, adolescents of the selected schools were the target population of the survey [13]. Based on specific ethnic and geographical characteristics in Taiwan, we designated the Mountain areas, the Northern, the Central, the Southern, and the Eastern areas. A ‘probability proportional to population size’ method was used to select 74 schools (5–6 from each stratum) randomly. From each school, in turn, 54–60 students were drawn randomly, stratified by gender and age. A total of 2204 adolescents (1093 boys and 1111 girls) participated in this survey. Serum UA levels vary widely in different gender due to the uricosuric effects for oestrogen. More than 90% of Chinese girls have reached menarche at age of 14 years, and the peak period of spermarche occurred from 12 to 14 years of age [14]. The adolescents, aged 14–19 years, who underwent a physical examination and had available questionnaire information and biochemistry data were eligible for inclusion in the present analysis. We excluded the adolescents who reported to have underlying diseases (e.g. liver, kidney, thyroid, etc.) and who were on medication (corticosteroids, Chinese herbal medicine, etc.).
Timing of puberty and reserve capacity in adolescence as pathways to educational level in adulthood—a longitudinal study
Published in Annals of Human Biology, 2019
Paulyn Jean Acacio-Claro, Leena Kristiina Koivusilta, David Teye Doku, Arja Hannele Rimpelä
We acknowledge some methodological limitations related to one of the pathways and the outcome variable studied. Age at spermarche or first ejaculation may not be an accurate indicator of pubertal onset, due to a high number of false negative results (Euling et al. 2008), which possibly diluted the effect of boys’ pubertal timing on adult education level in our study. The use of additional puberty markers, such as Tanner staging based on the appearance of secondary sexual characteristics, either through self-assessment or staging by a professional, was recommended for collection of puberty data (Euling et al. 2008), although this was not possible through mailed questionnaires. Still, the pubertal timing ages estimated in our study population closely resembled those described in other European countries which used more accurate staging methods for the same period (de Muinich Keizer and Mul 2001). For the outcome, we initially tried to use three categories of education (low, middle and high) where SEM results are ordered logistic regression coefficients. However, our current data did not support the proportional odds assumption required for the ordered three-category outcome. On the other hand, treating the categories as unordered or multinomial did not allow assessment of indirect effects, which is one of our main hypotheses. Thus, we decided to dichotomise adult education. Future research should assess if similar pathways operate for other categories of education such as middle education.
The First Ejaculation: A Male Pubertal Milestone Comparable to Menarche?
Published in The Journal of Sex Research, 2020
A main limitation of using spermaturia as a measure of male puberty is, naturally, the high rate of false negatives. The researchers in Copenhagen attempted to account for this issue with a statistical model relating the first observed spermaturia to the true spermarche (Jørgensen, Keiding, & Skakkebaek, 1991), but this model is seldom used, and employing the first observed spermaturia as a measure of male puberty is fading away. While spermarche may serve as a comparable fertility milestone to ovularche, a psychosomatic milestone comparable to menarche would be the first ejaculation itself. As such, attempts are now being made to characterize thorarche directly despite it being a less objective task than measuring spermaturia.