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Effect of HIV
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Simian virus 40 (SV40) is a monkey virus that was introduced into the human population by contaminated poliovaccines. The vaccines were produced in SV40 infected monkey cells between 1955 and 1963. The site of latent infection in humans is not known but the presence of SV40 in urine suggests the kidney as a possible site of latency. SV40 is a small DNA virus that is studied extensively because it is able to transform and immortalize multiple cell types (Ozer 2000, Saenz-Robles et al. 2001).
Polyoma viruses infect mammals causing tumors and cancer. Similarly to polyoma viruses, SV40 contains a DNA that is associated with histones in a circular complex containing 20- 22 nucleosomes (Varshavsky et al., 1977). SV40 DNA is located in a 50 nm capsid which is composed of homopentameters of the major capsid protein, VP1 (43 kilo Daltons) associated with one of the minor structural proteins VP2 or VP3. Under physiological salt and pH conditions, VP1 alone remains disassociated, and at pH 5, it assembles into tubular structures. Between pH 4 and pH 7, VP2 allows the VP1 pentameters to assemble in spherical particles and incorporates VP1. Furthermore, the virus has an icosahedral symmetry and contains 72 pentameters (Liddington et al., 1991). Figure 1shows the proposed structure of SV40 DNA and the length of each region within the virus. The diagram highlights the arrangement of the early and late regions. Furthermore, it shows the clockwise and counter clockwise symmetry of the large T antigen (TAg), small T antigen (tag), and the major capsid proteins within the virus.
Figure 1: diagram of the SV40 virus genome.
In 1989, Fogleman et al. analyzed the uncoating and penetration of Simian virus (SV 40). It uses the ganglioside...
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Takahashi, Y., et al. “Analysis of Promoter binding by the E2F and pRB Families In Vivo: Distinct E2F Proteins Mediate Activation and Repression.” Genes 14 (2000): 804-816.
Türler, Hans, and Consuelo Salomon. "Simian Virus 40 as a Vector: Recombinant Viruses Expressing Individual Polyoma T Antigens." Virus research 54.2 (1998): 133-45. .
Varshavsky, A.J., et al. “Compact form of SV40 Viral Minichromosome is Resistant to Nuclease: Possible Implications for Chromatin Structure.” Nucleic acids research 4 (1977): 3303-3325.
Vilchez, R.A. “Association between Simian Virus 40 and non-Hodgkin Lymphoma.” Lancet 359 (2002): 817-823.
Wang, Chih-Hung, et al. "Simian Virus 40 T Antigen Induces p53-Independent Apoptosis but does Not Suppress erbB2/neu Gene Expression in Immortalized Human Epithelial Cells." Cancer letters 137.1 (1999): 107-15.
Del Puerto, H. L., Martins, A., Vasconcelos, A. C., Milsted, A., Souza-Fagundes, E. M., Braz, G. F., et al. (n.d.). Canine distemper virus induces apoptosis in cervical tumor derived cell lines. http://www.virologyj.com/content/8/1/334. Retrieved January 29, 2014, from http://eds.b.ebscohost.com/eds/pdfviewer/pdfviewer?sid=c0b3ec67-82b8-411a-a30b-
Cytomegalovirus (CMV) is the most common virus in the United States that can infect almost any individual. Cytomegalovirus is also referred to as Herpesvirus-5, which belongs to a branch of Herpesviridae family. Herpesviridae has a spherical shape that contains four significant elements that are important to the viron. The four elements are the core, tegument, capsid and the envelope. Alphaherpesvirinae, Betaherpesvirinae and Gammaherpesvirinae are three subfamilies which belong to Herpesviridae. Cytomegalovirus belongs to the Betaherpesvirinae family, which also include Muromegalovirus and Roseolovirus. The Alphaherpesvirinae subfamily includes Simplexvirus, Varicellovirus, Mardivirus and Iltovirus genera. The Gammaherpesvirinae subfamily contains Lymphocryptovirus and Rhadinovirus genera. The diameter size of the virus is based on each specific family; however, the core remains the same throughout the species, which contains single layer of double stranded DNA tightly condensed in the capsid. In the tegument component, there are 30 or more viral proteins that are shapeless that encompass the capsid. Out of the four major components, the tegument has the most poorly defined structure. On the other hand, the capsid is a well-defined structure that is an icosahedron, which is composed of 162 capsomeres, 12 of which are pentons and 150 are hexons (1). Last but not least, the liquid envelope surrounds the tegument with approximately 10 glycoprotein and cellular proteins. Each subfamily under the herpesviriade has its own arrangement between the liquid envelop and the tegument layer.
Scientists are stumped as to the development and nature of proteinaceous infectious particles. Neither virus nor bacteria, these prions, are believed to cause transmissible spongiform encephalopathies (TSE), rare diseases said to be 100% fatal, without possessing nucleic acids. Their unhindered growth is thought to be the cause for bovine spongiform encephalopathy (BSE), or Mad Cow Disease, Creutzfeldt-Jakob (CJD), scrapie and other TSE, diseases characterized by the brain microscopically turning into sponge-like matter. There are no cures or effective treatments available today because drawbacks constantly prevent the development of efficient therapy. Studies continue to slowly progress, hoping to find methods to immunize against more prion diseases.
3. In the same month in which Gallo's and Essex's groups reported their data, Luc Montagnier and his colleagues from the Pasteur Institute, described the isolation of a retrovirus, later known as Lymphadenopathy Associated Virus (LAV), from the lymph nodes of a homosexual patient with lymphadenopathy.(5) Although this virus was similar to HTLV-I, one of its proteins, a protein with a molecular weight of 24,000 (p24), did not react with monoclonal antibodies to the HTLV-I p24 protein. Samples of this virus were, on several occasions, sent to Gallo's laboratory.
The virus is primarily spherical shaped and roughly 200nm in size, surrounded by a host-cell derived membrane. Its genome is minus-sense single-stranded RNA 16-18 kb in length. It contains matrix protein inside the envelope, hemagglutinin and neuraminidase, fusion protein, nucleocapsid protein, and L and P proteins to form the RNA polymerase. The host-cell receptors on the outside are hemagglutinin and neuraminidase. The virus is allowed to enter the cell when the hemagglutinin/ neuraminidase glycoproteins fuse with the sialic acid on the surface of the host cell, and the capsid enters the cytoplasm. The infected cells express the fusion protein from the virus, and this links the host cells together to create syncitia.
In humans and other eukaryotes, there is an extra step. RNA polymerase can attach to the promoter only with the help of proteins called basal (general) transcription factors. They are part of the cell's core transcription toolkit, needed for the transcription of any
Thought to be an oncogene, a gene that has potential in transforming normal cells into tumor cells, p53 was regarded as the most prominent tumor suppressor gene [1]. P53 is a gene which signals apoptosis (programmed cell death) if a cell cannot be repaired due to an extensive amount of damage. As stated in the textbook, p53 regulation occurs by an E3 ubiquitin-protein ligase known as MDM2 [1]. "Controlling the controller" is a statement that describes the molecular interaction where the presence of MDM2 targets the p53 for proteosome via degradation. With three main checkpoints in cell cycle, the literature states p53 functioning from G1 into S phase in a chaotic cell [2]. The normal state of cells is to keep p53 levels low in order to prevent uncontrolled apoptosis and random cell cycle arrest from occurring. In a further note, although p53 promotes apoptosis and cell cycle arrest, cancer may result from p53 unable to recognize the problematic site. In turn, a mutation in p53 may result engaging in new activities. These activities include cellular transformation, tumor metastasis,...
Jonas Salk, a virologist at the National Foundation for Infantile Paralysis (NFIP), used inactivated viruses (virus particles grown in culture and then killed by a form of heat) to create a polio vaccine. Salk drew blood from about two million children, which the NFIP checked for immunization. Through the collection of many HeLa cells and trial and error, the polio vaccine was ready in a year.... ... middle of paper ... ...
Newbold, R. F. (2002). The significance of telomerase activation and cellular immortalization in human cancer. Mutagenesis, 17(6), 539-550.
The hanta virus is not a new foe to humanity. This mysterious and sometimes fatal disease has plagued humanity for over 1000 years. This virus, most likely originating in China over 1000 years ago, is transmitted by human contact with mice. Only relatively recently has the hanta virus captured the attention of the United States. Although the hanta virus has been known for such a long time, there is little known about the virus. In the United States most cases are found in the southwestern part of the country, although cases have been reported from all four corners of the country. Recently, there have been successful tests done on prospective vaccines for the hanta virus. Despite this, strains of the hanta virus kill many people a year for lack of an effective medicine or vaccine (www.pharminfo.com).
The polio virus which causes poliomyelitis in humans is an enterovirus which belongs to the picornavirus (small, RNA) family. Polio virus is rapid, acid-resistant, stable, highly tissue specific and consists of a single-stranded, positive RNA. Polio virus is able to reside in the throat or intestinal tract of humans. Poliomyelitis is a highly contagious infectious disease which has three strains, poliovirus 1 (PV1), PV2 and PV3. Polio virus, although rare in developed countries, can be found in many under-developed countries due to the uncommonness of vaccinations there. Polio is known as a disease of development. The oldest known record of polio is in an Egyptian stone engraving of a young priest from 1350 B.C. with a withered leg, characteristic of a polio survivor. Loeffler and Frosch were the first individuals to see polio in 1898. The largest US epidemic was in 1916 in New York City.
Tumpey, T. M. (2005). Characterization Of The Reconstructed 1918 Spanish Influenza Pandemic Virus. Science, 310(5745), 77-80.
Many new viruses are emerging from the rainforest every year. The deadly viruses include the Ebola, Marburg, and AIDS viruses. They are some of the most destructive and lethal viruses that human kind has ever seen. They seem to affect most of the body and it?s organs with some rather gruesome symptoms. Although most die ending their suffering, some survive to relay the story of their pain. The Marburg virus described in “The Hot Zone” , by Richard Preston, exemplifies these new gruesome viruses well.
The length of the virus structure is of about 180 nm with a cross-sectional diameter of about 75 nm. Like a bullet, one end of the virus is rounded and the other end is planar or concave. The genome encodes 5-proteins: nucleoprotein (N), phosphoprotein (P), matrix protein (M), glycoprotein (G), and polymerase (L). The two major structural components of viruses like rabies that fall under the rhabdoviruses family are: a helical ribonucleoprotein core (RNP) and a surrounding envelope. Rabies is an RNA virus.
SARS is a virus of an animal, from wild or domestic animals that were used for food supplies. This virus is from a coronavirus family. T...