Sperm competition does not occur in flowering plants as typically only a single pair of sperm cells is delivered for double fertilization. Two recent reports show that plants are capable of avoiding reproductive failure when defective sperm cells are released.

Recently we reported that mouse germ cells in the testis contain active P450 aromatase (P450arom), the enzyme that converts androgens to estrogens. This finding suggested that germ cells have the ability to produce estrogen. Further studies have shown that germ cells in the testis of several species contain P450arom. The goal of this study was to determine if epididymal sperm contain P450arom a...

conclusions these results suggest that serum cholesterol, phospholipids and triacylglycerols have no effect on the levels of cholesterol, phospholipids and triacylglycerols of spermatozoa and seminal plasma. our findings suggest that sperm lipid content is regulated locally within the male reproductive tract. patients and methods cholesterol, phospholipids and triacylglycerols in sperm cells, s...

Background: Vitamin E is believed to be the primary component of the antioxidant system in spermatozoa. There is a relationship between activity of these antioxidant and function of sperm. Vitamins E and C which are belong to non-enzymatic antioxidant are used as a supplemented drug to improve sperm quality and male fertility. The present study was carried out to investigate the positive effect...

Antisperm antibodies were assessed in the serum samples of 73 men unable to ejaculate naturally and on the sperm cells of 13 of these men. None of the serum samples were found to be positive by sperm agglutination or sperm immobilization methods and antibodies were detected by an immunobead assay on the sperm cells of one of the 13 men examined.

Sperms are highly specialized cells for delivering DNA from male to the ovum. Incredibly, wide degree of diversity in sperm morphology in their basic structures i.e. head, middle piece and tail is found across species. Differences in terms of overall size of the sperm, shape and number of sperm produced are also incredible. One of the key for this variations or diversity in sperm may be associa...

objective: adiponectin and its receptors (adipor1 and adipor2), known as adiponectin system, have some proven roles in the fat and glucose metabolisms. several studies have shown that adiponectin can be considered as a candidate in linking metabolism to testicular function. in this regard, we evaluated the correlation between sperm mrna abundance of adiponectin and its receptors, with sperm mot...

Background: Male infertility is defined as an inability to impregnate a fertile female; it is a widespread problem which is usually caused by some male factors such as low quantity and quality of sperm, specifically oligospermia and azoospermia. Objective: This study aimed to evaluate the bio-positive effects of low power density Wi-Fi radiation on the reproductive system of infertile and...

BACKGROUND A key role of estrogens in human sperm biology has been recently suggested by aromatase and estrogen receptor detection in human testicular germ cells and ejaculated spermatozoa. However, the involvement of these hormones in the sperm maturation process is still not defined. The aim of this work was to investigate the expression of estrogen receptors, ER-alpha and ER-beta, in human e...

BACKGROUND Human sperm chemotaxis to pre-ovulatory follicular fluid is well established in vitro. However, it is not known whether the female's oocyte-cumulus complex secretes sperm chemoattractants subsequent to ovulation (for enabling sperm chemotaxis within the Fallopian tube) and, if so, which of these cell types--the oocyte or the cumulus oophorus--is the physiological origin of the secret...