Nowadays, a lot of research teams are trying to develop new ways to treat cancer or to improve the efficacy of already existing treatment strategies. To do this, it is important to understand the differences between tumor tissue and healthy tissue. One of these differences concerns the pH in cancerous environment. In normal cells, intracellular pH is generally around 7,2 and thus lower than the extracellular pH of 7,4. Cancer tissue however shows a reversed pH gradient: the intracellular pH is increased (>7,4) and the extracellular pH is lower than usual (6,7-7,1). This gradient is maintained thanks to changes in the expression and activity of some particular plasma membrane ion pumps and transporters that facilitate the H+ efflux. Due to the increased intracellular pH, cell proliferation and the evasion of apoptosis is possible and the metabolic adaption is facilitated. Moreover, for efficient directed cell migration a higher intracellular pH is even obligatory. The decreased extracellular pH also offers some advantages for the development of the tumor : HCO3—-dependent buffering is limited, extracellular matrix remodeling is promoted and acid-activated proteases are stimulated which makes tumor cell invasion and dissemination easier (Webb e.a. 2011).
Another difference between tumor tissue and normal tissue is the glutathione concentration. Glutathione (GSH) is composed of three amino acids: cysteine, glycine and glutamate (see Figure 1.1). It is a very important antioxidant and is present in virtually every cell of the human body. The concentration of GSH is much higher intracellular (0,5-10 mM) than in the extracellular milieu (2-20 µM), and in tumor tissue GSH concentration is at least 4-fold higher than in normal tissue (F...
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...degree of intermolecular association. By adjusting the formulation or the chemical moieties of the drug delivery system, the moment and the location of the release of the drug may be controlled (You e.a. 2010).
The term nanocarriers includes a wide range of different nanosized drug delivery systems. The oldest and at the same time the most clinically established nanocarriers are liposomes, spheres composed of an aqueous core surrounded by one or more concentric lipid bilayers. They are suited for the encapsulation of both hydrophillic and hydrophobic drugs, respectively in the aqueous core and whitin the lipid membrane (Hafner e.a. 2014). Liposomes increase thus the solubility of hydrophobic compounds, they enable trapping of drug molecules with a high potency, they reduce systemic side effects and toxicity and they attenuate drug clearance (Riehemann e.a. 2009)
More hydrogen ions in a solution is a result of lower pH, while fewer hydrogen ions in a solution is a result of increased pH. Meaning that a lower pH level results in a higher enzyme activity reaction and a higher pH level results in a lower enzyme activity reaction (Christianson, 2011 ).
Vemuri S. & Rhodes CT., 1994. Preparation and characterization of liposomes as therapeutic delivery systems: a review. Pharmaceutics Acta Hebetiae, 70, 95-111.
Early diagnosis provides the best hope many have in beating cancer. Unfortunately, this is not the end of the fight for many cancer patients. Primary tumors may be successfully treated early, only to later discover they have metastasized to other areas of the body.
Chemotherapy is the treatment of a tumor with chemical agents to reduce mass or eradicate a tumor completely. There are certain mechanisms by which chemotherapy inhibits cancer. The first mechanism is cell death by cytotoxicity. Some chemical agents in certain amounts are toxic to cells. The cells die due to the toxic...
In this case study, our concern goes for the chitosan nanoparticles; firstly nanoparticles are able to adsorb and/or encapsulate a drug, thus protecting it against chemical and enzymatic degradation. Furthermore the encapsulated drug may be prevented from crystallization, thus forming a solid solution. Depending on drug solubility in the carrier, a drug load varying from only a few percent up to 50%] Secondly, chitosan is ...
I have chosen to write about the constellation Cancer (The Crab). I chose Cancer because it is one of only a handful of constellations that I am actually able to identify in the night sky. Cancer is one of the twelve Zodiac constellations; people whose birthdays fall between June 21st and July 22nd have Cancer as their sign. Cancer is the Latin word for crab, and despite the fact that the constellation looks more like a lobster then a crab, it is still referred to as a crab. The constellation is visible from the northern hemisphere from late winter to early spring.
Cancer starts when certain cells in the body are mutated or changed and begin to divide. Cancerous cells grow differently than normal cells, instead of progressing through the normal cell lifecycle, cancer cells continue to grow and create more abnormal cells. A specific trait of cancer cells is that they have the ability to infiltrate and grow into surrounding tissues, developing out of control and causing serious damage to the host (Vincent, 2008). Cells become cance...
On a cellular level, Mrs. Jones’ cells are dehydrated due to osmotic pressure changes related to her high blood glucose. Cells dehydrate when poor cellular diffusion of glucose causes increased concentrations of glucose outside of the cell and lesser concentrations inside of the cell. Diffusion refers to the movement of particles from one gradient to another. In simple diffusion there is a stabilization of unequal of particles on either side of a permeable membrane through which the particles move freely to equalize the particles on both sides. The more complex facilitated diffusion is a passive transport of large particles from a high concentration of particles to a lower concentration of particles with the aid of a transport protein (Porth, 2011). The cellular membranes in our bodies are semipermeable allowing for smaller molecules to flow freely from the intracellular to extracellular space. The glucose molecule, however; is too large to diffuse through the cellul...
Discuss the possible drug and excipient-related constrains of the formulation (no identity of the drug was given to you at this
According to Cancer.org, cancer is the generic name for over a hundred diseases. There are cancers for literally every part of the body. Cancer starts by abnormal cells growing out of control. Usually, if the cancer is caught earlier in the stages, it is treatable and a person would have a good chance at surviving. Unfortunately, if the cancer is untreated for a longer duration of time, the survival rate dwindles. There are types of this abnormal cell growth that can be potentially more fatal than others. There is an astonishing amount of different cancers to delve in to. The chance of survival depends on the type, as well as the amount of time it has gone untreated.
The Effect of pH on Enzyme Activity. pH is a measure of the concentration of hydrogen ions in a solution. The higher the hydrogen ion concentration, the lower the pH. Most enzymes function efficiently over a narrow pH range. A change in pH above or below this range reduces the rate of enzyme reaction. considerably.
Cancer develops when cells in a part of the body begin to grow out of
Nanotechnology includes nanorobots which are so small that they can be injected into the human bloodstream after which the nanorobots can do investigations or repair at cellular level. Nanorobots could optimize the delivery of pharmaceutical products, these means that medicines which are targeted on a specific type of cells can be delivered to only those cells by the nanorobots. The robots can attach to the cells after which they can inject the drug into the target cells. This could be a great breakthrough for cancer treatments such as chemotherapy because there is a minimal chance of injecting healthy cells with the drug and therefor negative side effects can be avoided.
Blood and urine based biomarkers used in molecular pathology are only indicative of the average response of the cell population affected with little or no information of the range of response or variability form areas of tissue (Naddler and Langley 2001)
Enhanced Nutrient Delivery: Nano-encapsulating improves the solubility of antioxidants, vitamins, healthy omega oils and other neutraceuticals