Ultrasonographic evaluation of the rete testis thickness:a promising approach to differentiate obstructive from nonobstructive azoospermia

This study aimed to evaluate the ability of rete testis thickness(RTT)and testicular shear wave elastography(SWE)to differentiate obstructive azoospermia(OA)from nonobstructive azoospermia(NOA).We assessed 290 testes of 145 infertile males with azoospermia and 94 testes of 47 healthy volunteers at Shanghai General Hospital(Shanghai,China)between August 2019 and October 2021.The testicular volume(TV),SWE,and RTT were compared among patients with OA and NOA and healthy controls.The diagnostic performances of the three variables were evaluated using the receiver operating characteristic curve.The TV,SWE,and RTT in OA differed significantly from those in NOA(all P≤0.001)but were similar to those in healthy controls.Males with OA and NOA were similar at TVs of 9–11 cm^(3)(P=0.838),with sensitivity,specificity,Youden index,and area under the curve of 50.0%,84.2%,0.34,and 0.662(95%confidence interval[CI]:0.502–0.799),respectively,for SWE cut-off of 3.1 kPa;and 94.1%,79.2%,0.74,and 0.904(95%CI:0.811–0.996),respectively,for RTT cut-off of 1.6 mm.The results showed that RTT performed significantly better than SWE in differentiating OA from NOA in the TV overlap range.In conclusion,ultrasonographic RTT evaluation proved a promising diagnostic approach to differentiate OA from NOA,particularly in the TV overlap range.

Regulation of fertilization in male rats by CatSper2 knockdown

Interest in ion channels as drug targets for contraception has grown with the realization that certain ion channel subunits are located exclusively in sperm. Selective knockdown of ion channel subunits can lead to infertility without ill effects, and selective inhibitors and/ or openers of these ion channels could interfere with sperm function. In this study, in vivo electmporation （EP） and rete testis microinjection-mediated plasmid DNA were adopted to silence CatSper2 expression, which is essential in sperm hyperactivation. The results showed that high transfection efficiency and expression were achieved by plasmid DNA that was directly injected into the rete testis. As a result of the expression of CatSper2 being blocked, the treatment group showed significantly lower （P〈0.05） hyperactivation rate, fertilization rate in vitro, migration motility in viscoelastic solution and intracellular Ca2＋ peak. The low hyperactivation and fertilization rates lasted for 60 days. Meanwhile, analysis of the sperm survival rate and testis histology indicated that in vivo EP had no significant effect on the function of the testis, spermatogenesis or sperm activity. The present study demonstrated that it was feasible to achieve male contraception by silencing the expression of CatSper2, the key protein involved in sperm hvoeractivation.