Effects of oral exposure to silver nanoparticles on the sperm of rats.

It has been demonstrated that exposure to silver nanoparticles (AgNPs) can induce toxicological effects in rodents. In this study, we investigated whether sub-chronic oral exposure to different doses of polyvinil pyrrolidone (PVP)-coated AgNPs (PVP-AgNPs) (50, 100 and 200mg/kg/day) could induce harmful effects on epididymal sperm rat parameters. Sperm motility, viability and morphology were examined. Moreover, a histological evaluation of testis and epididymis was also performed. High doses of PVP-AgNPs showed higher sperm morphology abnormalities, while a progressive, but not significant effect, was observed in other sperm parameters. The current results suggest that oral sub-chronic exposure to PVP-AgNPs induces slight toxicological effects in sperm rat parameters.

Clinical experience with an artificial spermatocele.

Artificial spermatoceles were implanted into three patients with congenital absence of the vas. In each case, the testicular biopsy demonstrated normal spermatogenesis, and the dilated epididymal tubule was packed with spermatozoa. The ciliated epididymal mucosa appeared normal despite the tubular dilatation. The spermatoceles were constructed of expanded polytetrafluoroethylene, and they were microsurgically implanted over the cut end of the epididymis. The grafts were aspirated monthly for up to six months, and the aspirates containing spermatozoa were used for artificial insemination. Spermatozoa were consistently retrieved from each patient, but no pregnancies have resulted. The most obvious finding was that the spermatozoa lacked motility. In the discussion, other problems related to artificial spermatoceles are reviewed, including epididymal development and sperm maturation, aspiration techniques, and sperm storage.

Experimental studies on the functional capacity of the alloplastic spermatocele (Kelâmi-Affeld prosthesis).

An alloplastic spermatocele is implanted to obtain spermatozoa from the epididymis. It is known that, in an alloplastic spermatocele, spermatozoa deteriorate qualitatively and quantitatively as the time interval after implantation increases. 39 Kelâmi-Affeld alloplastic spermatoceles were implanted at the epididymal heads in minipigs. Castration and pathological-anatomical examination of the specimens were performed weeks to months after the operation. It became evident that fibrosis and granulation tissue in the area of the incised epididymal head with occlusion of the opened epididymal tubuli were the causes of aspermia developing in all cases. Apart from normal wound healing, there is additional formation of fibrosis and granulation tissue due to postoperative microbleeding and inflammatory reactions. It may be possible to reduce these complications by microsurgical techniques.

Direct profiling and imaging of peptides and proteins from mammalian cells and tissue sections by mass spectrometry.

Mass spectrometry can be used to map the distribution of targeted compounds in tissue, providing important molecular information in many areas of biological research. Matrix assisted laser desorption/ionization - time of flight - mass spectrometry (MALDI-TOF-MS) is well suited for the analysis of tissue samples with a spatial resolution of about 30 microm for compounds in a mass range from 1000 to over 50 000 Da. Direct analysis of tissue sections requires spotting or coating of the tissue with a matrix compound typically sinapinic acid or other cinnamic acid analogs. A raster of this sample by the laser beam and subsequent mass analysis of the desorbed ions can record molecular intensities throughout the section. The overall process is illustrated by profiling and imaging of mouse epididymis sections where protein activity changes markedly throughout the section.

Studies with an intravas nylon device in rat.

Contraceptive efficacy of an intravas device (IVD) was investigated in rat. The IVD used consisted of a nylon suture which did not occlude the lumen of the vas completely and permitted a free passage of spermatozoa. Its presence for periods ranging from 15 to 180 days did not produce any changes in the histology of the testis and epididymis; In the vas deferens the tall columnar ciliated epithelium was replaced by squamous epithelium. A spermatic granuloma developed on the vas at the entry of the IVD and its frequency of occurrence and size increased with the passage of time. The device caused an increase in the vasal protein, sialic acid and phospholipid content, and a decrease in the level of glycogen and alkaline phosphatase activity at 15 days. The level of portein, glycogen and alkaline phosphatase activity returned to normalcy at 90 days but the sialic acid and phospholipid content remained elevated. Notwithstanding these alterations the device failed to affect the spermatozoal number, morphology, motility and their fertilizing ability. The significance of these findings is discussed.