Can we identify a compound that could be added to spermatozoa in vitro Assignment

Can we identify a compound that could be added to spermatozoa in vitro to enhance their motility - Assignment Example In particular, sperm motility is an important parameter because it indicates the integrity of the sperm tail and axoneme structures as well as the status of mitochondrial metabolic machinery (Saharkhiz et al., 2013). The World Health Organization uses a 40% cut off as the lower limit of progressive sperm motility. Although the exact cause of asthenospermia is not clear, there is growing evidence that it may arise due to hyper-viscosity of semen, varicoceles, autoimmunity of the sperm cell, and necrospermia resulting from immotile cilia (Kartagener) syndrome (Saharkhiz et al., 2013). Overall, reduced sperm motility indicates epididymal or testicular failure that can be caused by various factors. Currently, treatment of male infertility has focused mainly on the traditional in vitro fertilization (IVF) approach and newer interventions such as micro-epididymal sperm aspirations and microsurgical fertilization. However, these techniques are uncommon in andrological practice. Current research efforts in this area focus on the use of chemical stimulation of spermatozoa. A number of chemicals can stimulate sperm motility including the addition of compounds known to exhibit phosphodiesterase inhibition (PDEI) activity to enhance sperm motility in vitro without compromising sperm morphology and function. PDEIs are a class of related compounds such as pentoxifylline (PTX) that selectively catalyze the hydrolysis of 3’ phosphate bond in cyclic Adenosine Monophosphate (cAMP) phosphate or cyclic Guanosine Monophosphate (cGMP). In one of the pioneering studies on in vitro stimulation of sperm motility, Shen (1991) demonstrated that Pentoxifylline (PTX) increases motility (velocit y) of ejaculated human spermertozoa both in in vitro aesthenozoospermic samples in oral therapy. Related studies have shown that PTX added in sperm suspensions increases sperm motion within 10 days with the motility characteristics persisting

Before Sunset Essay Example | Topics and Well Written Essays - 1000 words

Before Sunset - Essay Example The movie has rightfully earned great critical acclaim for portraying the lives of two individuals, who love each other dearly but are always pulled apart because of their circumstances. Moreover, it was not just the plot of the story that was laudable but the premise of the film further entails several themes regarding the geographical and urban design of the contemporary society that has greatly isolated people and restricted interaction on a daily basis. Even in the past, films were tools that were used vastly as a means to promote a particular city or culture. The entire filming before sunrise was done in Paris, providing insight into how urban structure seems to have affected the lives of the masses. The film depicts the life of both the protagonists and the degree to which their lives had changed over the period of their separation. Both Jesse and Celine portray contemporary individuals, who experience the rising problems of an urban society; loneliness being one of the primary issues. This concept is called urban isolation, which arises as a result of the layout of our society that prevents social encounters and interactions. From architecture to the overall communication network, modern civilization has been developed in such a way to protect the privacy of individuals that besides making things easier for people often results in people becoming more and more distant from each other. As a matter of fact, from residential buildings to everyday travel, privacy and seclusion are marketed as an asset and this feature is being made more attractive that makes people want to achieve it. This aspect is ostensible in the movie through the segregation that is believed to have been prolonged because of this aspect of the society. From the first movie, both of them had been heading towards opposite directions, although their circumstances kept them from reaching out to each other, but the period of their separation was further