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Endocrine Therapies
Published in David E. Thurston, Ilona Pysz, Chemistry and Pharmacology of Anticancer Drugs, 2021
In humans, the two forms of the estrogen receptor are encoded by different genes, ESR1 and ESR2 on the sixth and fourteenth chromosome (6q25.1 and 14q23.2), respectively. Due to alternative RNA splicing, several ER isoforms are also known to exist. Both ERs are widely expressed in different tissue types, although there are some notable differences in their expression patterns. For example, ERα is found predominantly in the endometrium, ovarian stromal cells, the hypothalamus, and in breast cancer cells. It is also found in the epithelium of the efferent ducts in the testes of men. The ERβ protein has been documented in the lungs, intestinal mucosa, prostate, kidney, brain, bone, and heart, and in ovarian granulosa and endothelial cells. To date, at least three ERα and five ERβ isoforms have been identified, some of which have specific functions. For example, the ERβ isoform subtypes can only transactivate transcription when a heterodimer with the functional ERß1 receptor of 59 kDa is formed, and the ERß3 receptor has been detected at high levels in the testes.
The Infertile Male
Published in Arianna D'Angelo, Nazar N. Amso, Ultrasound in Assisted Reproduction and Early Pregnancy, 2020
Thoraya Ammar, C. Jason Wilkins, Dean C.Y. Huang, Paul S. Sidhu
Ultrasound is almost always the initial imaging investigation in male infertility, with superb resolution aiding accurate assessment. Testicular morphology, patency of the efferent ducts, and prostatic anomalies are readily identified, and erectile dysfunction may be ascertained with a dynamic investigation. Ultrasound techniques used are as follows: Scrotal ultrasound B-mode, color and spectral Doppler ultrasound, and contrast-enhanced ultrasound (termed multiparametric ultrasound) [4]Transrectal ultrasoundB-Mode and dynamic color and spectral Doppler ultrasound of the penis
Regulation of Reproduction by Dopamine
Published in Nira Ben-Jonathan, Dopamine, 2020
A germ cell entering meiosis undergoes two consecutive cell divisions but only one replication of chromosomes. The first cell division (meiosis I) is dominated by a prolonged prophase (24 days in humans), while the second (meiosis II) resembles regular mitosis except that it is not proceeded by DNA replication. As they undergo cell divisions and cytoplasmic reorganization and differentiation, the germ cells progressively migrate away from the walls of the seminiferous tubules toward the lumen (Figure 10.8). From there, fully formed spermatozoa move to the rete testes and efferent ducts and into the epididymis, where they undergo additional maturation.
Distribution pattern of ZO-1 and claudins in the epididymis of vampire bats
Published in Tissue Barriers, 2020
Mariana M. Castro, Bongki Kim, Patrícia D. Games, Eric Hill, Clóvis Andrade Neves, José Eduardo Serrão, Sylvie Breton, Mariana Machado-Neves
Four epididymal regions, initial segments, caput, corpus, and cauda, were considered for evaluating the expression pattern of TJs’ proteins along the D. rotundus’ epididymis. Particularly, the initial segments were subdivided into the proximal (pIS), near to the efferent duct, and the distal portion (dIS), located between the pIS and caput region. In order to identify clear cells and basal cells in the epididymal epithelium, chicken V-ATPase B1 subunit antibody was used for clear cell identification,27 and a rabbit polyclonal KRT5 antibody (Abcam, Cambridge, MA, USA) was used for basal cell identification. 27,30 The secondary antibodies used in the double immunolabeling were CY3-conjugated donkey anti-chicken and Alexa 488-conjugated goat anti-rabbit IgG, respectively (Jackson ImmunoResearch Laboratories, West Grove, PA, USA).27 Confocal images were acquired on a Nikon A1 R confocal microscope with NIS Elements (Nikon Instruments), followed by analyzes with NIS Elements, Volocity 6 (v.6.3.1, Perkin Elmer), and Adobe Photoshop. Negative controls in which the primary antibody was omitted were included in immunofluorescence studies (Supplementary Figure S1).
Testing for genetic contributions to infertility: potential clinical impact
Published in Expert Review of Molecular Diagnostics, 2018
Csilla Krausz, Francesca Cioppi, Antoni Riera-Escamilla
In spite of the importance of CFTR mutations in CBAVD in about 20% the of cases, the origin of this condition is unknown. Recently, by performing whole exome sequencing, a new candidate gene has been identified in CBAVD [21,22]. It is the adhesion G protein-coupled receptor G2 (ADGRG2) gene, located on chromosome Xp22.13 and specifically expressed within the efferent ducts [23], in which most of the testicular fluid carrying immature spermatozoa is reabsorbed. Previous studies have demonstrated that Adgrg2 mutant male mice develop fluid accumulation in the testis ducts leading to an obstructive infertility phenotype, which is similar to that described in ADGRG2 mutation carriers. To date, five pathogenic ADGRG2 variants were reported, accounting for 11–15% of the CBAVD patients who are CFTR negative [21,22]. For this reason, ADGRG2 testing should be requested in CFTR-negative patients in order to rule out the X-linked transmission of this disease. The analysis of this gene could be done contemporarily with the NGS-based CFTR mutation screening.
Biological therapy for non-obstructive azoospermia
Published in Expert Opinion on Biological Therapy, 2018
Sarah C. Vij, Edmund Sabanegh, Ashok Agarwal
SSC injection is the other method of transfer to the recipient. The rete testis, efferent ducts, or the seminiferous tubules have been identified as injection targets for SSCs in several species [12]. Upon injection, the SSCs migrate to the basement membrane of seminiferous tubules and subsequently self-renew and differentiate to establish spermatogenesis in the recipient. This process should theoretically allow for conception without the requirement of assisted reproductive techniques, which is a major advantage. Hermann et al. injected adult rhesus monkey SSCs into the rete testes of recipient prepubertal rhesus monkeys and showed that mature spermatozoa were present in the ejaculate when they reached maturity. These spermatozoa demonstrated fertilizing capabilities when used with ICSI [13].