Introduction : Liposomes were discovered in the early 1960 by Bangham and colleagues (Bangham et al., 1965 ) and subsequently became the most extensively explored drug delivery system. Liposomes are concentric bilayered vesicle in which an aqueous volume is entirely enclosed by a membranous lipid bilayer mainly composed of natural or synthetic phospholipids. A liposome can be formed at a variety of sizes as uni-lamellar or multi-lamellar construction, and its name relates to its structural building blocks, phospholipids, and not to its size. Liposomes are artificially prepared vesicles made of lipid bilayer. The name liposome is derived from two Greek words: 'Lipos' meaning fat and 'Soma' meaning body. A liposome does not necessarily have lipophobic contents, such as water, although it usually does. Liposomes can be filled with drugs, and used to deliver drugs for cancer and other diseases. Liposomes can be prepared by disrupting biological membranes, for example by sonication. Liposomes are micro particulate or colloidal carriers, usually 0.05- 5.0 μm in diameter which form spontaneously when certain lipid are hydrated in aqueous media. Liposomes are composed of relatively biocompatible and biodegradable material, and they consist of an aqueous …show more content…
The hydrophobic tail is composed of two fatty acid chains containing 10-24 carbon atoms and 0-6 double bonds in each chain. The polar end of the molecules is mainly phosphoric acid bound to a water-soluble molecule. The hydrophilic and hydrophobic domains/segments within the molecular geometry of amphiphilic lipids orient and self organize in ordered supramolecular structure when confronted with solvents. The macroscopic structures most often formed include lamellar, hexagonal or cubic phases dispersed as colloidal nanostructures referred to as liposomes, hexasomes or cubosomes,
Due October 19th, 2015 Erin Gibbs: 200270053 Dr. Andrew Cameron Bio 222 Written Assignment 1 1. Health officials realized that the mysterious illness was not caused by a bacterium because the pathogen would be identified quickly in comparison to a virus, which is more complicated (CBC, 2013). 2. It was hard to identify the infectious agent because SARS presented as flu-like symptoms with a rapid onset and is similar to the common flu (CBC, 2013). People who had other underlying health problems made it difficult to identify symptoms of SARS because it made it hard to differentiate (CDC, 2013).
Biology 15 Lab # 3 Professor Passerini September 23, 2015 Scot Albert Lab #3 Questions 1, 2a, 3, 4, 5, 6a, 7, and 8 Table 3.1 - all columns except the last one. -------------------------------------------------- 1- a-Upside down and backwards b- If you move it right, the image moves left If you move it left, the image moves right c -
Paragraph 1: Margaret Sanger was the nation’s most important birth control supporter in the early twelfth century. She also committed her life to legalizing birth control and making it available for women all over. Sanger vulgarized the term “birth control”, opened the first birth control clinic into the United States, and established organizations that evolved into Planned Parenthood. (Jody) Paragraph 2: In 1924, the title red-string used to open Band-Aid.
Testing for the Presence of Macromolecules in McDonald’s Happy Meals Clayton Wagoner MST Biology White 4 duPont Manual High School Introduction Carbohydrates, lipids, proteins, and nucleic acids are organic molecules found in every living organism. These macromolecules are large carbon based structures. The macromolecules are assembled by joining several smaller units, called monomers, together through a chemical reaction called dehydration synthesis. The resulting polymer can be disassembled through the complementary process called hydrolysis.
Introduction The purpose of this lab is to use control variables to help identify different macromolecules. Biological systems are made up of these four major macromolecules: carbohydrates, lipids, proteins and nucleic acids. Carbohydrates are sugar molecules (monosaccharides, disaccharides, and polysaccharides) which make them the most abundant macromolecule on the earth. Lipids (oils and fats, phospholipids and steroids) are insoluble in water and perform many functions such as energy source, essential nutrients, hormones and insulators (Lehman, 1955).
Liposuction first originated when a French surgeon Charles Dujarier first introduced the concept of body contouring and fat removal in 1920. Back then the surgeries were very unsuccessful and had deadly consequences. The first attempt of liposuction was done to a famous French ballerina dancer Mademoiselle Geoffre. She had desired more attractive knees and calves to make herself more alluring as a dancer and liposuction was the way to achieve this, but the operation took a turn for the worse when she had contracted gangrene and had to amputate her legs which shortly after lead to her death, there is always a price to pay for beauty.
The olestra molecule is much larger than natural fats and cannot be broken down by normal digestive processes neither in the small not in the large intestine. It cannot be absorbed across the intestinal wall nor can it be metabolized
C) Describe the chemical composition of the plasma membrane and relate it to membrane function. The plasma membrane is the outer limiting membrane of a cell that separates the body’s two major fluid components, the intercellular fluid that is within cells and the extracellular fluid outside of cells. It is very thin, about 7 to 10 nm, and is composed of a bilayer of lipid molecules with proteins dispersed in it. The phospholipid bilayer is composed of a portion that is hydrophilic, or attracted to water, and a portion that is hydrophobic, or water avoiding.
It is rapidly deaminated by cytidine deaminase to biologically inactive uracil arabinoside (Ara-U), and is eliminated in urine. Thus the drug is administered through continuous intravenous injection. Plama protein binding of the drug is 13% and it is metabolized in the liver. Some effective formulations and cytarabine derivatives that are not easily deaminated and with better pharmacokinetic patterns, are used. The drug is encapsulated into pharmacologically acceptable carriers to protect it from rapid degradation and elimination, eg: encapsulation of cytarabine into multivesicular liposomes for intrathecal treatment of lymphomatous meningitis, minimizes its conversion into Ara-U, as stated by Japanese researcher Akinobu Hamada et al, in
However, the narrow therapeutic window and multiorgan toxicity has limited it from further clinical use. In order to increase its therapeutic index, different kinds of triptolide-loaded delivery systems have been developed, which has been verified to change the pharmacokinetics of triptolide and decrease the toxicity. The pharmacokinetic study of a triptolide-loaded delivery system in mice showed that a targeted tissue accumulation and longer residence time were found in triptolide-loaded lipid emulsion [62]. The AUC0-t of triptolide-loaded lipid emulsion increased 2.19 folds, suggesting that the triptolide-loaded lipid emulsion does improve the biodistribution, accumulation and therapeutic efficacy in pancreas. Moreover, the levels of triptolide-loaded lipid emulsion in heart, lung and kidney were lower than that of the triptolide group, which would reduce the toxicity of triptolide in the above tissues.
The basic role of sustained release drug delivery system is to achieve a steady state drug in blood for the extended period of time. The design of proper dosage regimens is an important element in accomplishing this goal. In case of injectable dosage forms, this period may vary from day to months. In the case of oral administrated dosage forms, this period is measured in hours and critically depends on the residence time of the dosage form in the gastrointestinal tract. Products of this type have been formulated for oral injectables and topical use and inserts for placement in the body cavities[2].
This diagram identifies the eukaryotic cell is more evolved than the prokaryotic cells and has a more complicated structure. Eukaryotic cells are what makeup animals and plants. Unlike the prokaryotic cells most eukaryotic cells contain a nucleus surrounded by nucleoplasm within its own membrane and the eukaryotic cell contains many more types of organelles than the prokaryotic cell. The nucleus contains the DNA of the cell and coordinates the cells functions that include growth, reproduction, metabolism and protein synthesis. On the edge of the nucleus are nuclear pores, this allows the nucleus to communicate with the rest of the cell, found within the nucleus is the nucleolus a dense structure of a crystalline protein and nucleic acid used
There are many different structures within the eukaryotic cell, and they have many specific functions. This enables the cell to perform efficiently. Eukaryotic cells include cells found in both plants and animals, and for that reason, there are variations on what the cell can include. I will be focusing mainly on animal cells, however there are structures that appear in both cells.
Biochemically, the cytoskeleton is defined as a remnant of the cell after treatment with non-ionic detergents, which looks like an empty cage of the cell. Cytoskeleton
There are two kids of ER; the rough ER which is studded with ribosomes that synthesize proteins and smooth ER that lacks ribosomes for lipid synthesis. The ribosomes are also found in all cells and are small bodies free or attached to ER. They are used for protein synthesis. The mitochondria are an organelle that carries out cellular respiration producing ATP molecules. The lysosome breaks down larger food molecules into small molecules, and also contains enzymes used to digest old cell parts.