Search

A formal C‒H addition of N-heteroaromatics to aldehydeswas achieved using a binary hybrid catalyst system comprising an acridinium photoredox catalyst and a thiophosphoric acid organocatalyst. The reaction proceeded through the following sequence: 1) photoredox-catalyzed single-electron oxidation of a thiophosphoric acid catalyst to generate a thiyl radical, 2) cleavage of the formyl C‒H bond of the aldehyde substrates by a thiyl radical acting as a hydrogen atom transfer catalyst to generate acyl radicals, 3) Minisci-type addition of the resulting acyl radicals to N-heteroaromatics, and 4) a spin-center shift, photoredox-catalyzed single-electron reduction, and protonation to produce secondary alcohol products. This metal-free hybrid catalysis proceeded under mild conditions for a wide range of substrates, including isoquinolines, quinolines, and pyridines as N-heteroaromatics, as well as both aromatic and aliphatic aldehydes, and tolerated various functional groups. The reaction was applicable to late-stage derivatization of drugs and their leads.

A hybrid system accomplishing cooperativity between an organophotoredox acridinium catalyst and a chiral chromiumcomplex catalyst was developed, enabling the unprecedented exploitation of unactivated hydrocarbon alkenes as precursors to chiral allylchromium nucleophiles for the asymmetric allylation of aldehydes. The reaction proceeded under visible light irradiation at room temperature and with high functional group tolerance, affording the corresponding homoallylic alcohols with up to >20/1 diastereomeric ratio and 99% ee. The addition of Mg(ClO4)2 elicited profound enhancement of both reactivity and enantioselectivity.

Summary. A 30-year-old male attended the Toyama Medical and Pharmaceutical University Hospital with the chief complaint of infertility. Physical examination showed bilateral small testes and the semen contained no sperm. Hormonal studies revealed hypergonadotropic hypogonadism and cytogenetic studies showed a 46, XX karyotype. High-resolution banding showed no abnormalities in both of the X chromosomes. Histological examination of both testes showed germinal aplasia and the proliferation of Leydig cells. The diagnosis of XX-male was made from the above findings. A DNA hybridization study using 17Y-specific probes revealed the presence of a major part of the short arm of the Y chromosome, which had presumably been translocated to the X chromosome. The translocated Y short arm had a small deletion within it.

Summary To measure testicular volume accurately, an ultrasonographic method was developed and the results obtained from this compared with those obtained by conventional measurements, namely (1) comparison with testis models, (2) an orchidometer, and (3) measurement of testicular volume by calipers through the scrotal skin. Data from these methods were compared with the actual volume measured at operation by slide calipers placed directly on the testis. The volume obtained by comparison with testis models or with an orchidometer tended to overestimate the actual volume. The volume measured by slide calipers on scrotal skin was also found to be incorrect. On the other hand, the volume measured by ultrasonography proved to be closer to, and to correlate well with, the actual volume, and was considered to be the best method.

Seventeen patients with hydrocele of the testis were treated by aspiration of fluid and substitution with tetracycline supplemented with 1% lidocaine. In 15 patients (88%) symptoms disappeared by sclerotherapy. After sclerotherapy scrotal ultrasonography was useful to diagnose either relapse or thickened tunica vaginalis. No side effect was noticed.

The ultrasonograms obtained from 20 cases with testicular tumors were reviewed to correlate the ultrasonographic findings with the histologic features. Some seminomas and all metastatic tumors (leukemia, malignant lymphoma and prostatic cancer) showed homogeneous and hypoechoic findings ultrasonographically. All nonseminomatous germ cell tumors had heterogeneous findings on ultrasonography. In patients with leukemia or malignant lymphoma, ultrasonography can serve as a marker in assessing the efficacy of chemotherapy or in the early diagnosis of recurrence. Scrotal ultrasonography also seems to be useful in detecting the small tumor and seems to be convenient for the follow-up of the contralateral testis of a patient who has undergone extirpation of a testicular tumor.

Ejaculated spermatozoa from an infertile patient were examined by scanning and transmission electron microscopy. All spermatozoa had abnormalities in the tail region. The abnormalities were divided into three types: (a) spermatozoa with a spherical tail. The tail was larger than the head in volume. This type of abnormality accounted for about 60% of the population; (b) spermatozoa with a blunt tail. The tails were about 2 microns in diameter and about 7 microns in length. This type of abnormality accounted for about 30% of the population of an ejaculate; (c) spermatozoa without a tail. Some of these had only a rudimentary tail. About 10% of the population belonged to this type. In types A and B, all components of the tail, except for dynein arms, were observed, but they were severely disarranged. Biopsy specimens of the testes and of the nasal mucosa of this patient were also investigated. The testicular biopsy showed defects in manchette formation. Normal development of the manchette could not be observed. The nasal epithelium showed absence of the inner dynein arms in the cilia.

Summary A case of headless or decapitated spermatozoa of an infertile man is reported. The 33-year-old patient showed almost normal spermi-ogram except for a high percentage (more than 90%) of headless spermatozoa. Both hypoosmotic swelling and zona-free hamster egg tests showed that most headless spermatozoa appeared to be normal in their function as tails. The ultrastructure of the ejaculated spermatozoa was observed using a surface replica method and by conventional ultrathin sectioning. The headless spermatozoa were almost normal in structure except for the absence of the head. Tailless heads were rarely observed. Varieties of ultrastructural abnormalities were observed in spermatozoa heads. Among them, abnormalities in the nuclear membrane covering the posterior pole of the nucleus were prominent. The implantation fossa and the basal plate were not formed. Instead, the nuclear membrane with numerous nuclear pores was found in this region. The decapitation seemed to take place between the region of the basal plate and the proximal centriole.