Monday, February 24, 2020

Medical Biochemistry Essay Example | Topics and Well Written Essays - 2500 words

Medical Biochemistry - Essay Example Substances levels can give a lot of information to healthcare professionals, in both clinical and research settings. Lactate dehydrogenase (LDH) is present in many human tissues, enabling cells to undergo anaerobic glycolysis; its main cellular function, conversion of pyruvate into lactate, provides the energy production cycle with more substrates. Normal and abnormal levels are now standardized, and measuring its activity in serum/plasma will help elucidate the origins of damage or disease. There are different isoenzymes of LDH, which differ in their structure and certain other properties. In this practical work, which is divided into 3 weeks, we will first make a comparison of the absorption spectra of NAD+ and NADH, since the assay for LDH makes use of an important difference in these spectra. In addition, the linearity of the LDH assay, with respect to the amount of enzyme, will be assessed, and the limit of linearity determined. In week two, we will assess the LDH isoenzyme profile in rat serum and selected tissues, using agarose gel electrophoresis. Finally, the total LDH activity will be determined, using its natural substrate pyruvate. LDH activity will also be measured using the substrate analogue Nicotinamide adenine dinucleotide (NAD) is a coenzyme, a molecule which aids an enzyme in the acceleration of a chemical reaction, or catalysis. NAD is an agent that accepts electrons from other substrates; when NAD is reduced, the reaction forms NADH, a molecule that can be used as a donator of electrons. In aerobic glycolysis, for instance, energy is produced in the form of 2 adenosine triphosphates (ATP); in order to produce the adequate amount of energy the body cells need, the cellular mitochondria utilizes NADH. The inner membranes of this organelle are impermeable to NADH, so the latter is re-oxidized to NAD and delivers its electrons to certain shuttles that are able to transfer the substrate into the mitochondria. By these means, cytoplasmic NADH is oxidized and yields 3 ATP molecules, much more energy to the cell. Many other enzymes produce NADH in the mitochondria, all of which can be oxidized in the electron transport chain and in the process, capture energy for ATP synthesis. Once the NADH has been oxidized, the NAD can again be used by enzymes that require it, including those of the citric acid cycle (Krebs's cycle), and pyruvate dehydrogenase, among others. 2. Compare and comment on the distribution of the LDH isoenzyme bands within the tissues. Glycolysis is a biochemical cascade that coverts the main body fuel, glucose, into two pyruvates, releasing energy. In certain cells, where oxygen lacks, glycolysis occurs anaerobically: red blood cells, skeletal muscle, etc. Lactate dehydrogenase (LDH) is an enzyme that is only used in anaerobic processes. By converting pyruvate to lactate, it reoxidizes NADH to NAD, so that a new reaction can be started using this coenzyme. This is an important function of LDH, because energy production would stop without NAD substrates. According to Brancaccio

Saturday, February 8, 2020

Anemia Research Paper Example | Topics and Well Written Essays - 2500 words

Anemia - Research Paper Example It happens when our body fails on making healthy Red Blood Cells and leads to fatal diseases like cancer, thalassemia etc (Uthman 4). To understand how anemia gets itself rooted within a person’s body it becomes important to first understand what is the importance of Red Blood Cells in our body and why their deficiency cause anemia. It is a common assumption that human body has large proportion of blood but this is not true. Actually, blood makes up only a small fraction of our body’s volume i-e blood accounts for only seven present of the total body volume. Various systems in our body hugely depend upon blood circulation and its confinement most importantly the Circulatory system and Reticuloendothelial System (Uthman 7). Blood may appear to be like an inert liquid to the naked eye but in real sense it is living and breathing tissue just like any other body part. It consists of cells suspended in a liquid medium. Plasma is that liquid medium which accounts for about 60 percent of the total blood volume and it comprises of 93 percent water (Uthman 9). Besides water, it also consists of two types of proteins called albumin and globulins. Plasma also contains proteins that are involved in the coagulation of blood and are called coagulation factors. If we take plasma out of the blood and let it clot or coag ulate then the resulting fluid is called serum. The quantity of nutrients and other substances in serum helps evaluating anemia during laboratory testing. Forty percent of total blood volume is constituted by Blood Cells and the Red Blood Cells (RBCs or Erythrocytes) formulate the largest proportion while the other constituents are the White Blood Cells (Leukocytes) and Platelets. RBCs have nuclei in the DNA and are self-replicating cells that are made in the bone marrow. RBCs account for half of the total blood cells in the body and their only