Partial male-to-female reprogramming of mouse fetal testis by Sertoli cell ablation.

Temporal transcription profiles of fetal testes with Sertoli cell ablation were examined in 4-day culture using a diphtheria toxin (DT)-dependent cell knockout system in AMH-TRECK transgenic (Tg) mice. RNA analysis revealed that ovarian-specific genes, including Foxl2, were ectopically expressed in DT-treated Tg testis explants initiated at embryonic days 12.5-13.5. FOXL2-positive cells were ectopically observed in two testicular regions: near the testicular surface epithelia and around its adjacent mesonephros. The surface FOXL2-positive cells, together with ectopic expression of Lgr5 and Gng13 (markers of ovarian cords), were derived from the testis epithelia/subepithelia, whereas another FOXL2-positive population was the 3ßHSD-negative stroma near the mesonephros. In addition to high expression of Fgfr1/Fgfr2 and heparan sulfate proteoglycan (a reservoir for FGF ligand) in these two sites, exogenous FGF9 additives repressed DT-dependent Foxl2 upregulation in Tg testes. These findings imply retention of Foxl2 inducibility in the surface epithelia and peri-mesonephric stroma of the testicular parenchyma, in which certain paracrine signals, including FGF9 derived from fetal Sertoli cells, repress feminization in these two sites of the early fetal testis.

A novel Amh-Treck transgenic mouse line allows toxin-dependent loss of supporting cells in gonads.

Cell ablation technology is useful for studying specific cell lineages in a developing organ in vivo. Herein, we established a novel anti-Müllerian hormone (AMH)-toxin receptor-mediated cell knockout (Treck) mouse line, in which the diphtheria toxin (DT) receptor was specifically activated in Sertoli and granulosa cells in postnatal testes and ovaries respectively. In the postnatal testes of Amh-Treck transgenic (Tg) male mice, DT injection induced a specific loss of the Sertoli cells in a dose-dependent manner, as well as the specific degeneration of granulosa cells in the primary and secondary follicles caused by DT injection in Tg females. In the testes with depletion of Sertoli cell, germ cells appeared to survive for only several days after DT treatment and rapidly underwent cell degeneration, which led to the accumulation of a large amount of cell debris within the seminiferous tubules by day 10 after DT treatment. Transplantation of exogenous healthy Sertoli cells following DT treatment rescued the germ cell loss in the transplantation sites of the seminiferous epithelia, leading to a partial recovery of the spermatogenesis. These results provide not only in vivo evidence of the crucial role of Sertoli cells in the maintenance of germ cells, but also show that the Amh-Treck Tg line is a useful in vivo model of the function of the supporting cell lineage in developing mammalian gonads.

Current awareness and use of transthoracic echocardiography in evaluation of valvular heart disease in Kumamoto Prefecture -a report from the Kumamoto cardiovascular echocardiography standardization project.

BACKGROUND: There are few reports on transthoracic echocardiography (TTE) for the evaluation of valvular heart disease in a specific area or region. METHODS AND RESULTS: This cross-sectional questionnaire-based survey was conducted in 2023 in Kumamoto Prefecture, where 106 hospitals provide cardiology services. Ninety-three (88%) of the hospitals completed questionnaires regarding TTE. The severity of low flow/low gradient AS was evaluated by dobutamine stress echocardiography in only 7% of hospitals and exercise stress echocardiography for asymptomatic mitral regurgitation in only 5%. Multivariate logistic regression analysis revealed that participation in remote multi-institutional echocardiographic meetings and use of the Kumamoto Prefecture echocardiographic manual were significantly associated with the use of a multi-window approach (P < 0.05). CONCLUSIONS: In Kumamoto Prefecture, echocardiographic measurements are performed according to the recommendations at a relatively low rate. Dissemination of recommendations through remote meetings and the use of the echocardiographic manual may increase the likelihood of TTE being performed according to the recommendations.

Current Awareness and Status of Venous Ultrasonography in Kumamoto Prefecture　- A Report of the Kumamoto Cardiovascular Echocardiography Standardization Project.

Background: There are few reports on the current awareness and status of venous ultrasonography, including the number of specialists who perform this procedure, in a specific regional area in Japan. Methods and Results: This cross-sectional survey study was conducted in Kumamoto Prefecture from October 2018 to March 2019. Of the 366 medical institutions providing cardiology services in Kumamoto Prefecture, 259 (101 general hospitals, 158 small clinics) responded to our questionnaire. In 2017, 21,773 venous ultrasound tests were performed, 21,101 (97%) of which were performed in hospitals and only 672 (3%) were performed in clinics. Both the number of institutions performing venous ultrasounds and the number of tests performed increased over time. Although 317 medical staff in Kumamoto Prefecture were performing transthoracic echocardiography (TTE) when the questionnaires were collected, only 210 performed venous ultrasounds. Although 91% (61/67) of medical institutions could perform TTE within 30 min, only 77% (53/69) performed venous ultrasounds within 30 min. The number of venous ultrasounds per population×100 was largest in the Kumamoto and Kamimashiki areas (1.67) and smallest in the Kamoto area (0.05). Conclusions: This is the first report to reveal the current awareness and status of venous ultrasonography in a specific region in Japan. There are several problems to be overcome, such as a lack of venous ultrasound specialists and the regional disparity in venous ultrasounds in Kumamoto Prefecture.

Current Awareness and Status of Transthoracic Echocardiography in Kumamoto Prefecture　- A Report of the Kumamoto Cardiovascular Echocardiography Standardization Project.

Background: There are few reports on current awareness and status of transthoracic echocardiography (TTE), including the actual performance rate according to echocardiographic guidelines, in a specific area or region. Methods and Results: This cross-sectional survey study was conducted in Kumamoto Prefecture from October 2018 to March 2019. There are 366 medical institutions advocating cardiology in Kumamoto Prefecture. Of these, 259 (101 hospitals and 158 clinics) returned questionnaires regarding TTE. In all, 150,570 TTEs were performed in 2017. Of these, 132,771 (88%) were performed in hospitals and 17,799 (12%) were performed in clinics. Physicians performed only 5% of TTEs, whereas sonographers performed 86%. Although the modified Simpson method was performed in 90% of hospitals, 3-dimensional echocardiography was performed in only 2% of hospitals. In addition, the left atrial volume index was not examined in approximately 60% of hospitals, and the mean E/E' ratio was not examined in 80% of hospitals. Multivariable logistic regression analysis revealed that having a Fellow of the Japan Society of Ultrasonic in Medicine was significantly and independently associated with guideline-oriented TTE (odds ratio 9.43; 95% confidence interval 1.22-72.71, P<0.05). Conclusions: The rate of echocardiographic measurements performed according to echocardiographic guidelines is exceptionally low in Kumamoto Prefecture. Sufficient dissemination of echocardiographic guidelines may be important in improving this rate.

Molecular and genetic characterization of partial masculinization in embryonic ovaries grafted into male nude mice.

In most of mammalian embryos, gonadal sex differentiation occurs inside the maternal uterus before birth. In several fetal ovarian grafting experiments using male host mice, an experimental switch from the maternal intrauterine to male-host environment gradually induces partial masculinization of the grafted ovaries even under the wild-type genotype. However, either host-derived factors causing or molecular basis underlying this masculinization of the fetal ovaries are not clear. Here, we demonstrate that ectopic appearance of SOX9-positive Sertoli cell-like cells in grafted ovaries was mediated by the testosterone derived from the male host. Neither Sox8 nor Amh activity in the ovarian tissues is essential for such ectopic appearance of SOX9-positive cells. The transcriptome analyses of the grafted ovaries during this masculinization process showed early downregulation of pro-ovarian genes such as Irx3, Nr0b1/Dax1, Emx2, and Fez1/Lzts1 by days 7-10 post-transplantation, and subsequent upregulation of several pro-testis genes, such as Bhlhe40, Egr1/2, Nr4a2, and Zc3h12c by day 20, leading to a partial sex reversal with altered expression profiles in one-third of the total numbers of the sex-dimorphic pre-granulosa and Sertoli cell-specific genes at 12.5 dpc. Our data imply that the paternal testosterone exposure is partially responsible for the sex-reversal expression profiles of certain pro-ovarian and pro-testis genes in the fetal ovaries in a temporally dependent manner.

Congenital absence of inferior vena cava with azygos continuation revealed by vascular echo in a patient with pulmonary thromboembolism and deep vein thrombosis: a case report.

A 44-year-old man with an isolated anomaly of azygos continuation of the inferior vena cava (IVC) presented with dyspnea due to pulmonary thromboembolism (PTE) and deep-vein thrombosis (DVT). Sono-graphic examination disclosed not only pulmonary hypertension and DVT, but also infrahepatic interruption of the IVC with azygos continuation. A rare anomaly of azygos continuation of IVC could cause DVT and PTE. Vascular echo could play an important role in the examination of DVT and/or venous anomalies.