The objective of the present study was to establish a method for nuclear replacement in metaphase-II (M-II) stage porcine oocytes. Karyoplasts containing M-II chromosomes (K) and cytoplasts without chromosomes (C) were produced from in vitro-matured oocytes by a serial centrifugation method. The oocytes were then reconstructed by fusion of one karyoplast with 1, 2, 3 or 4 cytoplasts (K + 1C, K ...

Understanding nutrient limitation of net primary productivity (NPP) is critical to predict how plant communities will respond to environmental change. Foliar nutrients, especially nitrogen and phosphorus concentrations ([N] and [P]) and their ratio, have been used widely as indicators of plant nutritional status and have been linked directly to nutrient limitation of NPP. In tropical systems, h...

Integrity of the sperm membrane, of which phosphatidyl serine (PS) plays a central role, is essential for fertilization. The externalisation of PS (EPS) occurs during capacitation and the acrosome reaction. EPS, from the inner to the outer membrane, is considered as a sign of early apoptosis. Therefore, EPS may have a dual function in sperm. This study has evaluated the relationship between EPS...

Drastic membrane reorganization occurs when mammalian sperm binds to and fuses with the oocyte membrane. Two oocyte protein families are essential for fertilization, tetraspanins and glycosylphosphatidylinositol-anchored proteins. The firsts are associated to tetraspanin-enriched microdomains and the seconds to lipid rafts. Here we report membrane raft involvement in mouse fertilization assesse...

The nuclear chromatin decondensation test (NCDT) detects the ability of the sperm chromatin to undergo decondensation following fertilization. The test does not have direct bearing with the fertilizing ability of the spermatozoa but only reflects the proportion of sperm that may swell following exposure to in vitro decondensing agents. The gross seminal parameters do not have any direct relatio...

background: conventional ivf and icsi are two common techniques to achieve fertilization. ivf has long been used for treatment of infertility, although it is not an effective treatment in severe male infertility. the use of icsi has been expanded in severe male factor and fertilization failure after ivf cycle. in spite of the widespread use of icsi in patients with non-male factor infertility, ...

In vitro fertilization (IVF) is widely used in reproduction research, but the sperm of some inbred strains of mice yield low fertilization rates in IVF. To determine the cause of this problem, we examined the effect of epididymal sperm morphology, in particular, tail bending and the presence and type of cytoplasmic droplet (CD), on fertilizability in vitro. Sperm suspensions were obtained from ...

A good functional status of cryopreserved boar spermatozoa is very important for successful fertilization of porcine oocytes and in vitro embryo production. The purpose of the study was to evaluate the changes in functional status of boar spermatozoa separated from frozen-thawed semen and capacitated in vitro by caffeine. The effect of acrosome reaction development in spermatozoa on the efficie...

The objective of this experiment was to evaluate spermatological parameters and fertilizing ability of short term stored semen in different extenders from endemic Abant trout (Salmo trutta abanticus T,1954). Semen was collected from 30 adult males by the hand stripping method without anesthesia. Having determined the main spermatological properties (volume, motility, movement duration, concentr...

OBJECTIVE This study aimed to assess predictive ability of heart rate variability (HRV) for pregnancy outcomes with in vitro fertilization (IVF) treatment. RESEARCH DESIGN AND METHOD A total of 180 women with 261 cycles of IVF and 211 embryo transfers (ETs) were analyzed. HRV was measured at four times during IVF treatment: the first date of menstruation, r-HCG (Ovidrel) administration, and b...