PPT-Viral Replication 5 th Lecture

Viral Replication Viruses multiply only in living cells As viruses are obligate intracellular pathogens they cannot replicate without the machinery and metabolism of a host cell The host cell must provide the energy and synthetic machinery and the lowmolecularweight precursors for the synthesis of viral proteins and nucleic acids . viruses. General description. Viruses is not living organism, as they lack two essential properties of life- they cannot . replicate. independently, and cannot . survive. long –term independently so it is obligate intracellular organism .. Bassyouni. VIROLOGY. An Introduction to the Viruses. 2. . Viruses are parasites at the genetic level. They are the smallest infectious agents known. They can infect man, animals, insects, plants and bacteria. The following properties distinguish viruses from other organisms:. Introduction to viruses . Viruses consist of a nucleic acid (either DNA or RNA) associated with proteins encoded by the nucleic acid. The virus may also have a lipid . bilayer. membrane (or envelope) but this is acquired from the host cell, usually by budding through a host cell membrane. If a membrane is present, it must contain one or more viral proteins to act as . Dalya. Basil. Antiviral Chemotherapy . (Prevention and Treatment of Viral Infection). Viruses are a leading cause of disease and death worldwide. Although public health measures and vaccines are the most effective ways to control many viral infections, preventive measures have not succeeded for numerous viral diseases. For some of these diseases, antiviral drugs have been developed.. where . are we now and . where . are we going? . Jintanat. Ananworanich, MD, PhD. Associate Director for Therapeutics Research. US Military HIV Research Program (MHRP). Maryland, USA. Deputy Director of SEARCH . Carcinogenesis. Carcinogenesis or . Oncogenesis. =. creation of cancer= normal cells are transformed into cancer cells= characterized by . a progression of changes on cellular and genetic level . that ultimately reprogram a cell to undergo uncontrolled cell division, thus forming a malignant mass.. . PATHOGENESIS. The. . study. . of. . viral. . pathogenesis elucidates. . this. . special. . relationship. . between. . the. . virus. . and. . the intact. . host.. . The. . term. . Lecture 1 and 2. Gene Therapy. Definition: . the . introduction of normal genes into cells in place of missing or defective ones in order to correct genetic disorders. .. Approaches: . Replacing a mutated gene that causes disease with a healthy copy of the gene.. BCH 4I4. LECTURE 7-9. Survey of structural properties of different classes of viruses . S.O Anadozie (Ph.D. .). VIRUSES. A virus is a small filterable and obligate intracellular parasite requiring a living host for its multiplication . Ori. Disclaimer. The information represents my understanding only so errors and omissions are probably rampant. It has not been vetted or reviewed by faculty. The source is our class notes.. The document can mostly be used forward and backward. I tried to mark questionable stuff with (?). .  . Antigenic drift. . where individual bases in the DNA or RNA . mutate. to other bases. Most of these . point mutations. are "silent" – they do not change the protein that the gene encodes. . Introduction:. Viral infections of plants can cause necrosis, hypoplasia . or . hyperplasia and these effects can lead to symptoms such as. Growth retardation . Distortion. Mosaic patterning of leaves. College of Medicine. ( Foundation Block ,. . Microbiology . : 2017) . Introduction to medical . virology. . بسم الله الرحمن الرحيم. OBJECTIVES.  . Distinguish the viruses from other microorganisms. Dr.Luma. . amer. Viral genetics. Viruses are simple . creatures, . lacking an . energy-generating system . and having very limited . biosynthetic capabilities. . The smallest viruses have only a . few genes.