The movement of the endocytosed protein which is destined for the apical surface to fuse with and also the movement of extracellular materials from one side of the epithelial cells to another can be termed as transcytosis. With respect to concept, transcytosis can be grouped into three processes namely; endocytosis, exocytosis and transcellular transport (Pravda,2011). Though transcytosis is tightly controlled by the cell it also has the potential for transepithelial movement of bacteria and other pathogens, hence it sometimes becomes an etiologic factor in the body(Pravda,2011). Trancytosis occurs in hepatocytes and this phenomenon is a typical example of transcellular transport . Here the apical membrane form bile and the basolateral membrane face blood.
For example, the forward scatter parameter reduces on cell shrinkage while nuclear condensation causes an increase in side scatter. Apoptotic cells can also be detected using hematoxylin and eosin staining, using light microscopy. Although this is a simple technique, it cannot detect apoptotic cells in early stages and the technique needs to be supplemented with other methods of detection. Transmission Electron Microscopy (TEM) is considered as the gold standard to confirm apoptosis. TEM can detect apoptotic bodies, phagocytosis of apoptotic bodies and nuclear fragmentation among other changes.
However this test has a low sensitivity where some individuals with low result would be considered to be deficient but show no clinical evidence of deficiency and conversely symptoms of deficiency can be seem when the result does not fall into the low range. There is a large ‘grey zone’ or ‘indeterminate range’ between normal and abnormal levels. In order to detect vitamin B12 deficiency, a more sensitive and specific screening test is required. Haptocorrin (HC) and transcobalamin (TC) are transport proteins for vitamin B12 . Transport of vitamin B12 to the tissues is brought about by TC.
Degradation of fibrin is performed by serine protease plasmin, which is present in blood as a proenzyme, plasminogen, and needs to be activated by tissue plasminogen activator (tPA) and urokinase. Disturbance in haemostasis with abnormal bleeding may be caused by thromocytopenia, platelet function disorder, or defects in blood coagulation. Vascular disorders might also cause a bleeding. To get an accurate diagnosis, which is crucial for successful treatment, the haemostatic function has to be examined. The information about the haemostatic function can by gained using a number of laboratory tests to assess platelet and coagulation
They are proteins that are complexly folded to allow smaller molecules to fit into them; this active site is where substrate molecules bind. Enzymes must collide with one another at a precise position with enough activation energy. The active site must bind to the reacting molecule, or the substrate (1). Enzyme-catalyzed reactions require lower activation energy. The activity of an enzyme is affected by its environmental factors, and any change results in an alteration in the rate of the reaction caused by the enzyme (2).
Dosage forms usually are made up of the active compound and other ingredients known as excipients. Excipients can have many functions, they can act as fillers, lubricants, binders, preservatives and antioxidants. A change in the nature of the excipients can significantly affect the stability of the active ingredient as well as its release from the dosage form. Changes in the preparation (the way the compound is made) of the active compound like the use of a different solvent for purification, can affect its bioavailability (The fraction of the dose of a drug that is found in general circulation around the body. It is influenced by such factors such as Absorption, Distribution, Metabolism and Elimination (ADME).
The thrombin also promotes platelet aggregation. The fibrin stabilizes the platelet aggregates forming a platelet-fibrin thrombus. The formation of this thrombus on the device is bad as it can block the flow of blood to crucial organs including the heart and it can have fatal consequences. Thrombus formation on artificial devices is the result of both platelet activation and
The integrity of a genome is monitored by several mechanisms including DNA damage checkpoints, DNA repair machinery, and mitotic checkpoints within the cell. If there are defects in any one of these mechanisms the result is genomic instability. A few other things that can alter the regulation of the cell cycle are posttranslational modifications of histone tails, chromatin structure, and DNA methylation. This topic continues to be a debate about what exactly the driving force of the initiation
In plant and fungi, microtubule organizing centre is called as Spindle Pole Body (SPB). All these microtubule organizing centers contain universally a tubulin homologue called γ-tubulin that interacts with α- and β-tubulin and helps in the nucleation of microtubule. In a cell, individual microtubule elongates and shrinks back or may completely disappear and is replaced by a new one. This process involves the polymerization and depolymerization with the hydrolysis of GTPs. The microtubule containing ADP-tubulin at the end is highly unstable and depolymerizes rapidly that is called “catastrophe” and the phenomenon is known as “dynamic
Others can overwhelm the body if applied in only one place, and are often cut into sections and applied to different parts of the body to avoid this, such as nitroglycerin. Many molecules, however, such as insulin, are too large to pass through the skin. Basic components of Transdermal drug delivery systems: 1. Polymer matrix: The mechanism of drug release depends upon the physicochemical properties of the drug and polymer used in the manufacture of the patches(17). These control the release rate of the drug from the patches.