Enzymatic hydrolysis and base analysis by high performance liquid chromatography showed that mouse satellite DNA had 30-50% less 5-methylcytosine in sperm than in somatic tissue (1.59 mols % vs 2.40-3.11 mols %). Maxam-Gilbert sequencing and analysis of the intensity of the cytosine bands indicated that the level of methylation of the eight CpGs of the consensus sequence in sperm satellite DNA ...

As sperm production is costly, males are expected to strategically allocate resources to sperm production according to mating opportunities. While sperm number adjustments have been reported in several taxa, only a few studies investigated whether sperm quality shows adaptive plasticity as well. We tested this prediction in the guppy, Poecilia reticulata. A total of 46 males were initially stri...

background: chromomycin a3 (cma3) staining has been used to assess protamine deficiency. the aim of this study was to determine credibility of cma3 along with semen parameters for assessment of fertility potential. materials and methods: semen analysis and cma3 staining were carried out on 234 fertile and 178 subfertile individuals. semen analysis was assessed according to who criteria. protami...

background: to evaluate predictive factors of successful microdissection-testicular sperm extraction (md-tese) in patients with presumed sertoli cell-only syndrome (scos). materials and methods: in this retrospective analysis, 874 men with non-obstructive azoospermia (noa), among whom 148 individuals with diagnosis of scos in prior biopsy, underwent md-tese at department of andrology, royan ins...

this is the first report implementing combined density gradient centrifugation/zeta (dgc/zeta) sperm selection procedure for a couple with eleven previous intra cytoplasmic sperm injection/ in vitro fertilization (icsi/ivf) failure cycles. semen analysis was carried out according to world health organization criteria. protamine deficiency, dna fragmentation and morphology were assessed by chrom...

Assessment of sperm has over the years by many been regarded as something secondary to assessment of ova, oocytes and embryos. Often the most inexperienced of the laboratory staff have been asked to evaluate the semen sample. It is our belief that the outcome of subfertility treatment could be improved considerably, if semen and sperm assessment would be taken more seriously. This may not be as...

In flowering plants, the two sperm cells are embedded within the cytoplasm of the growing pollen tube and as such are passively transported to the embryo sac, wherein double fertilization occurs upon their release. Understanding the mechanisms and conditions by which male gametes mature and take part in fertilization are crucial goals in the study of plant reproduction. Studies of gene expressi...

Segregation distortion has been reported to occur in a number of the trinucleotide repeat disorders. On the basis of a sperm typing study performed in patients of Japanese descent with Machado-Joseph disease (MJD), it was reported that disease alleles are preferentially transmitted during meiosis. We performed a sperm typing study of five MJD patients of French descent and analysis of the poole...

In this study, we conducted a simultaneous analysis of sperm count and viability in rats by flow cytometry (FCM). Epididymal fluids were taken from the caudal epididymis of 12 to 13 week-old Sprague-Dawley rats. The fluids were weighed and mixed with Dulbecco's phosphate buffered saline (D-PBS). Propidium iodide, which can stain only dead sperm, was used to distinguish viable and dead sperm. Th...