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Nupapillomavirus
''Nupapillomavirus'' is a genus of viruses in the family ''Papillomaviridae''. Humans serve as natural hosts. There is only one species in this genus: ''Nupapillomavirus 1''. Diseases associated with this genus include facial warts. This virus has also been detected in some skin carcinomas and premalignant keratoses. Structure Viruses in ''Nupapillomavirus'' are non-enveloped, with icosahedral geometries, and T=7 symmetry. The diameter is around 52-55 nm. Genomes are circular, around 8kb in length. Life cycle Viral replication is nuclear. Entry into the host cell is achieved by attachment of the viral proteins to host receptors, which mediates endocytosis. Replication follows the dsDNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ... bidirectional replication model. DN ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Papillomavirus
''Papillomaviridae'' is a family of non- enveloped double-stranded DNA viruses whose members are known as papillomaviruses. Several hundred species of papillomaviruses, traditionally referred to as "types", have been identified infecting all carefully inspected mammals, but also other vertebrates such as birds, snakes, turtles and fish. Infection by most papillomavirus types, depending on the type, is either asymptomatic (e.g. most Beta-PVs) or causes small benign tumors, known as papillomas or warts (e.g. human papillomavirus 1, HPV6 or HPV11). Papillomas caused by some types, however, such as human papillomaviruses 16 and 18, carry a risk of becoming cancerous. Papillomaviruses are usually considered as highly host- and tissue- tropic, and are thought to rarely be transmitted between species. Papillomaviruses replicate exclusively in the basal layer of the body surface tissues. All known papillomavirus types infect a particular body surface, typically the skin or mucosal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viruses
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898, more than 16,000 of the millions of virus species have been described in detail. The study of viruses is known as virology, a subspeciality of microbiology. When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent viral particles, or ''virions'', consisting of (i) genetic material, i.e., long molecules of DNA or RNA that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skin Cancer
Skin cancers are cancers that arise from the Human skin, skin. They are due to the development of abnormal cells (biology), cells that have the ability to invade or metastasis, spread to other parts of the body. It occurs when skin cells grow uncontrollably, forming malignant tumors. The primary cause of skin cancer is prolonged exposure to ultraviolet (UV) radiation from the sun or tanning devices. Skin cancer is the most commonly diagnosed form of cancer in humans. There are three main types of skin cancers: basal-cell skin cancer (BCC), squamous-cell skin cancer (SCC) and melanoma. The first two, along with a number of less common skin cancers, are known as nonmelanoma skin cancer (NMSC). Basal-cell cancer grows slowly and can damage the tissue around it but is unlikely to spread to distant areas or result in death. It often appears as a painless raised area of skin that may be shiny with telangiectasia, small blood vessels running over it or may present as a raised area wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-enveloped
A viral envelope is the outermost layer of many types of viruses. It protects the genetic material in their life cycle when traveling between host cells. Not all viruses have envelopes. A viral envelope protein or E protein is a protein in the envelope, which may be acquired by the capsid from an infected host cell. Host cell infection process Numerous human pathogenic viruses in circulation are encased in lipid bilayers, and they infect their target cells by causing the viral envelope and cell membrane to fuse. Although there are effective vaccines against some of these viruses, there is no preventative or curative medicine for the majority of them. In most cases, the known vaccines operate by inducing antibodies that prevent the pathogen from entering cells. This happens in the case of enveloped viruses when the antibodies bind to the viral envelope proteins. The membrane fusion event that triggers viral entrance is caused by the viral membrane fusion protein. Many enveloped v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Icosahedral
In geometry, an icosahedron ( or ) is a polyhedron with 20 faces. The name comes . The plural can be either "icosahedra" () or "icosahedrons". There are infinitely many non- similar shapes of icosahedra, some of them being more symmetrical than others. The best known is the (convex, non- stellated) regular icosahedron—one of the Platonic solids—whose faces are 20 equilateral triangles. Regular icosahedra There are two objects, one convex and one nonconvex, that can both be called regular icosahedra. Each has 30 edges and 20 equilateral triangle faces with five meeting at each of its twelve vertices. Both have icosahedral symmetry. The term "regular icosahedron" generally refers to the convex variety, while the nonconvex form is called a ''great icosahedron''. Convex regular icosahedron The convex regular icosahedron is usually referred to simply as the ''regular icosahedron'', one of the five regular Platonic solids, and is represented by its Schläfli symbol , containi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endocytosis
Endocytosis is a cellular process in which Chemical substance, substances are brought into the cell. The material to be internalized is surrounded by an area of cell membrane, which then buds off inside the cell to form a Vesicle (biology and chemistry), vesicle containing the ingested materials. Endocytosis includes pinocytosis (cell drinking) and phagocytosis (cell eating). It is a form of active transport. History The term was proposed by Christian de Duve, De Duve in 1963. Phagocytosis was discovered by Élie Metchnikoff in 1882. Pathways Endocytosis pathways can be subdivided into four categories: namely, receptor-mediated endocytosis (also known as clathrin-mediated endocytosis), caveolae, pinocytosis, and phagocytosis. * Clathrin-mediated endocytosis is mediated by the production of small (approx. 100 nm in diameter) vesicles that have a morphologically characteristic coat made up of the cytosolic protein clathrin. Clathrin-coated vesicles (CCVs) are found in vir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DsDNA
Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of all known organisms and many viruses. DNA and ribonucleic acid (RNA) are nucleic acids. Alongside proteins, lipids and complex carbohydrates (polysaccharides), nucleic acids are one of the four major types of macromolecules that are essential for all known forms of life. The two DNA strands are known as polynucleotides as they are composed of simpler monomeric units called nucleotides. Each nucleotide is composed of one of four nitrogen-containing nucleobases (cytosine guanine adenine or thymine , a sugar called deoxyribose, and a phosphate group. The nucleotides are joined to one another in a chain by covalent bonds (known as the phosphodiester linkage) between the sugar of one nucleotide and the phosphate of the next, resulting in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Host
In infectious disease ecology and epidemiology, a natural reservoir, also known as a disease reservoir or a reservoir of infection, is the population of organisms or the specific environment in which an infectious pathogen naturally lives and reproduces, or upon which the pathogen primarily depends for its survival. A reservoir is usually a living host of a certain species, such as an animal or a plant, inside of which a pathogen survives, often (though not always) without causing disease for the reservoir itself. By some definitions a reservoir may also be an environment external to an organism, such as a volume of contaminated air or water. Because of the enormous variety of infectious microorganisms capable of causing disease, precise definitions for what constitutes a natural reservoir are numerous, various, and often conflicting. The reservoir concept applies only for pathogens capable of infecting more than one host population and only with respect to a defined target popu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
