Peptidoglycan and Lipoteichoic Acidinduced Cell Activation Lab Report

Peptidoglycan and Lipoteichoic Acidinduced Cell Activation - Lab Report Example This can eventually lead to sepsis (Alberts et al 2002a). Previous work showed that in Gram negative bacteria lipopolysaccharide (LPN), a component of the outer membrane, activated a cell's immune response in this manner. It interacted with the Toll-like receptors types 2 and 4 (TLR2 and TLR4) present on host cell membranes (Kirschning et al 1998, Poltorak et al 1998, Quereshi et al 1999). The authors in this paper demonstrate how the components of Gram positive bacterial cell membranes stimulate cell activation through TLR2. The invasion of an organism's blood stream with bacteria often results in sepsis. Invasive bacteria will activate the host cell's immune system. Sepsis results from the inability of the immune system to limit bacterial spread during an infection. The inhibitory mechanisms controlling inflammation are over-ridden by the huge bacterial load on the cell. Inflammation during sepsis will then develop into a systemic syndrome with a number of clinical symptoms such as tissue injury, increased vascular permeability, dilation of blood vessels, loss of plasma volume and blood clotting, and, eventually, multi-organ failure and shock (Alberts et al 2002b, Decker 2004)). Initially bacteria bind to host cell membranes and this stimulates the systemic release of cytokines and other inflammatory signalling molecules into the blood. (Alberts et al 2002b). ... The mechanism for Gram negative bacterial mediated activation of the cell's immune response has been well documented (Alberts et al 2002). LPN within the bacterial cell wall binds to LPN binding protein present in serum and this complex in turn binds to the CD14 receptor (figure 4). The CD14 receptor is either soluble in serum or tethered to the host cell membrane through a GPI (glycophosphatidylinositol) anchor. Either way the CD14 receptor does not have an intracellular domain so it cannot transmit its signalling messages intracellularly. This observation suggested that another "co-receptor" acted in conjunction with the CD14 receptor to allow the transmission of an extracellular signal to the inside of the cell. The Toll-like receptors (TLRs) have an intracellular domain linking to the IL-1 signalling pathway. The Toll-like receptor acts to phosphorylate a cascade of kinases TRAF6, TAK-1, IKK and eventually the transcription factor NFB. NFB then translocates to the nucleus where i t activates the transcription of a number of genes involved in immune and inflammatory responses (Alberts et al 2002a, figure 5). In Gram negative bacteria the Toll-like receptors 2 and 4 has been shown to be intrinsic in cell activation (Kirschning et al 1998, Poltorak et al 1998, Quereshi et al 1999). In this paper the authors attempted to determine if components isolated from Gram positive bacteria activated cells in a TLR dependent manner. HEK293 cells were transfected with a number of Toll-like receptors alongside a luciferase reporter gene. A NFB transcription element was placed upstream of the luciferase reporter gene, such that activaiton of NFB would initiate transcription of luciferase. When luciferase

Subsidized in the city Essay Example | Topics and Well Written Essays - 750 words

Subsidized in the city - Essay Example Parents have pampered their children beyond imagination, they give their children credit cards which spoils them, they have the liberty to spend money on anything and everything that they like, entering adulthood in the real sense is no walk in the park, it comes with a lot of responsibilities which one must understand and fulfill, earning a substantial amount is extremely important, without that it is very difficult to survive in today’s world. The accommodation has become so expensive; the standard of living has gone up by manifolds and there are several other expenditures which one must take care of to be able to live a happy life. Above all there one should have self-respect, parents will always come to rescue their children but one must start drawing a line, becoming financially independent is extremely important these days, children should not only become financially independent but they should also help and support their parents in any which way plausible. Adults these days are not interested in changing their lifestyle, they are aware of the fact that they cannot refrain from going to posh places, shopping, watching movies so on and so forth, they should change their lifestyle and seek no help from their parents, an adult who is financially dependent has no respect and to earn respect one must refrain from spending excessively, parents who pay for their children after they become adults should completely stop helping them, they should try their best to make their children financially independent and they should also ensure that no money should be spent on their vices, adults have several vices these days, several adults are hooked on to drugs, alcohol and what not, parents must keep a strict check on all these vices which are more than capable of ruining one’s life. â€Å"There is something to be said for writing that rent check each month and knowing you've managed to live comfortably on your own terms. Racking up $500 shopping sprees on Mommy and Daddy's credit card may have its momentary allure, but the adult part of me believes that working for what you have is much more rewarding than being handed it on a silver platter. And I have my own mom and dad to thank for that.† (Subsidized in the City) Overspending is a major concern, adults should completely stop blowing up the hard-earned money of their parents on useless activities, they must keep a check on their spending only then will they become adults in the real sense otherwise they are just a bunch of over aged children who fail to understand what is expected of them. It is also important to understand the feelings of parents’, though they hardly say anything, deep down they know that they are spoiling the future of their children and making them overly dependent which is not good at all. Conclusion There is no counter argument possible on this topic, adults must manage their own expenses, they must also understand that their parents will not be around forever to keep helping them out, they must earn well and spend smartly, spending on useless things is hardly going to help them. It is high time for adults to realize their responsibility, they should be making their parents proud, and instead they are busy spending their hard-earned money. Spending money is perhaps the easiest job but earning it requires a lot of hard-work and dedication. The article is a well written; it comprehensively presents how