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Hepeviridae
''Hepeviridae'' is a family of viruses. Human, pig, wild boar, sheep, cow, camel, monkey, some rodents, bats and chickens serve as natural hosts. There are two genera in the family. Diseases associated with this family include: hepatitis; high mortality rate during pregnancy; and avian hepatitis E virus is the cause of hepatitis-splenomegaly (HS) syndrome among chickens. Taxonomy The following genera are assigned to the family: * ''Orthohepevirus'' * '' Piscihepevirus'' A third genus has been proposed — Insecthepevirus. This proposed genus contains one species — Sogatella furcifera hepe-like virus. A species — Crustacea hepe-like virus 1, has been isolated from a prawn (''Macrobrachium rosenbergii''). Structure Viruses in the family ''Hepeviridae'' are non-enveloped, with icosahedral and spherical geometries, and T=1 symmetry. The diameter is around 32-34 nm. Genomes are linear and non-segmented, around 7.2kb in length. The genome has three open reading frames. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepeviridae
''Hepeviridae'' is a family of viruses. Human, pig, wild boar, sheep, cow, camel, monkey, some rodents, bats and chickens serve as natural hosts. There are two genera in the family. Diseases associated with this family include: hepatitis; high mortality rate during pregnancy; and avian hepatitis E virus is the cause of hepatitis-splenomegaly (HS) syndrome among chickens. Taxonomy The following genera are assigned to the family: * ''Orthohepevirus'' * '' Piscihepevirus'' A third genus has been proposed — Insecthepevirus. This proposed genus contains one species — Sogatella furcifera hepe-like virus. A species — Crustacea hepe-like virus 1, has been isolated from a prawn (''Macrobrachium rosenbergii''). Structure Viruses in the family ''Hepeviridae'' are non-enveloped, with icosahedral and spherical geometries, and T=1 symmetry. The diameter is around 32-34 nm. Genomes are linear and non-segmented, around 7.2kb in length. The genome has three open reading frames. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthohepevirus
''Orthohepevirus'' is a genus of viruses assigned to the family ''Hepeviridae''. ''Orthohepevirus'' is a fairly isolated viral genus in which the virions are characterized by round, non-enveloped and isometric capsids with a diameter of 27–34 nm. The hepatitis E virus belongs this genus as the species ''Orthohepevirus A'' Genome Orthohepeviruses have RNA genomes of 7176 nucleotides in length and infect vertebrates. Additionally, the genome is monopartite, linear, and single-stranded. The genome is 5' capped with a poly A tail at the 3' end. The genome possesses three main open reading frames. The first encodes non-structural proteins, the second encodes the capsid proteins, and the third encodes a small, multifunctional protein. Taxonomy Viruses from this genus have been isolated from a variety of mammals (including rodents, mustelids and bats) as well as birds. At least three variants of avian hepatitis E virus have been isolated from birds. A Hepatitis E-like virus has bee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmission Electron Microscopy
Transmission electron microscopy (TEM) is a microscopy technique in which a beam of electrons is transmitted through a specimen to form an image. The specimen is most often an ultrathin section less than 100 nm thick or a suspension on a grid. An image is formed from the interaction of the electrons with the sample as the beam is transmitted through the specimen. The image is then magnified and focused onto an imaging device, such as a fluorescent screen, a layer of photographic film, or a sensor such as a scintillator attached to a charge-coupled device. Transmission electron microscopes are capable of imaging at a significantly higher resolution than light microscopes, owing to the smaller de Broglie wavelength of electrons. This enables the instrument to capture fine detail—even as small as a single column of atoms, which is thousands of times smaller than a resolvable object seen in a light microscope. Transmission electron microscopy is a major analytical method i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clathrin-mediated Endocytosis
Receptor-mediated endocytosis (RME), also called clathrin-mediated endocytosis, is a process by which cells absorb metabolites, hormones, proteins – and in some cases viruses – by the inward budding of the plasma membrane (invagination). This process forms vesicles containing the absorbed substances and is strictly mediated by receptors on the surface of the cell. Only the receptor-specific substances can enter the cell through this process. Process Although receptors and their ligands can be brought into the cell through a few mechanisms (e.g. caveolin and lipid raft), clathrin-mediated endocytosis remains the best studied. Clathrin-mediated endocytosis of many receptor types begins with the ligands binding to receptors on the cell plasma membrane. The ligand and receptor will then recruit adaptor proteins and clathrin triskelions to the plasma membrane around where invagination will take place. Invagination of the plasma membrane then occurs, forming a clathrin-coated pit. Ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oncorhynchus Clarkii
The cutthroat trout is a fish species of the family Salmonidae native to cold-water tributaries of the Pacific Ocean, Rocky Mountains, and Great Basin in North America. As a member of the genus ''Oncorhynchus'', it is one of the Pacific trout, a group that includes the widely distributed rainbow trout. Cutthroat trout are popular gamefish, especially among anglers who enjoy fly fishing. The common name "cutthroat" refers to the distinctive red coloration on the underside of the lower jaw. The specific name ''clarkii'' was given to honor explorer William Clark, coleader of the Lewis and Clark Expedition. Cutthroat trout usually inhabit and spawn in small to moderately large, clear, well- oxygenated, shallow rivers with gravel bottoms. They reproduce in clear, cold, moderately deep lakes. They are native to the alluvial or freestone streams that are typical tributaries of the rivers of the Pacific Basin, Great Basin and Rocky Mountains. Cutthroat trout spawn in the spring and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fomite
A fomite () or fomes () is any inanimate object that, when contaminated with or exposed to infectious agents (such as pathogenic bacteria, viruses or fungi), can transfer disease to a new host. Transfer of pathogens by fomites A fomite is any inanimate object (also called passive vector) that, when contaminated with or exposed to infectious agents (such as pathogenic bacteria, viruses or fungi), can transfer disease to a new host. Contamination can occur when one of these objects comes into contact with bodily secretions, like nasal fluid, vomit, or feces. Many common objects can sustain a pathogen until a person comes in contact with the pathogen, increasing the chance of infection. The likely objects are different in a hospital environment than at home or in a workplace. Fomites such as splinters, barbed wire or farmyard surfaces, including soil, feeding troughs or barn beams, have been implicated as sources of virus. Hospital fomites For humans, common hospital fomites are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoonosis
A zoonosis (; plural zoonoses) or zoonotic disease is an infectious disease of humans caused by a pathogen (an infectious agent, such as a bacterium, virus, parasite or prion) that has jumped from a non-human (usually a vertebrate) to a human. Typically, the first infected human transmits the infectious agent to at least one other human, who, in turn, infects others. Major modern diseases such as Ebola virus disease and salmonellosis are zoonoses. HIV was a zoonotic disease transmitted to humans in the early part of the 20th century, though it has now evolved into a separate human-only disease. Most strains of influenza that infect humans are human diseases, although many strains of bird flu and swine flu are zoonoses; these viruses occasionally recombine with human strains of the flu and can cause pandemics such as the 1918 Spanish flu or the 2009 swine flu. ''Taenia solium'' infection is one of the neglected tropical diseases with public health and veterinary concern in en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaky Scanning
Leaky scanning is a mechanism used during the initiation phase of eukaryotic translation that enables regulation of gene expression. During initiation, the small 40S ribosomal subunit (as a 43S PIC) "scans" or moves in a 5' --> 3' direction along the 5'UTR to locate a start codon to commence elongation. Sometimes, the scanning ribosome bypasses the initial AUG start codon and begins translation at further downstream AUG start codons.Kozak, Marilyn. “Initiation of Translation in prokaryotes and eukaryotes.” Gene 234 (1999): 187-208. Academic Search Complete. Web. 10 June 2014. Translation in eukaryotic cells according to most scanning mechanisms occurs at the AUG start codon proximal to the 5' end of mRNA; however, the scanning ribosome may encounter an “unfavorable nucleotide context” around the start codon and continue scanning.Herzog, Etienne., et al. “Translation of the Second Gene of Peanut Clump Virus RNA 2 Occurs by Leaky Scanning In Vitro.” Virology 208. (1995): ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alphatetraviridae
''Alphatetraviridae'' is a family of viruses. Moths and butterflies serve as natural hosts. There are two genera in the family. Infection outcome varies from unapparent to lethal. Taxonomy The following genera are assigned to the family: *''Betatetravirus'' *''Omegatetravirus'' Structure Viruses in ''Alphatetraviridae'' are non-enveloped, with icosahedral geometries, and T=4 symmetry. The diameter is around 40 nm. Genomes are linear and non-segmented, bipartite, around 6.5kb in length. Life cycle Viral replication is cytoplasmic. Entry into the host cell is achieved by penetration into the host cell. Replication follows the positive stranded RNA virus replication model. Positive stranded rna virus transcription is the method of transcription. Translation takes place by leaky scanning, and ribosomal skipping. Moths and butterflies serve as the natural host. Transmission routes are oral. References External links Viralzone: AlphatetraviridaeICTV {{Taxonbar, fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrovirus
Astroviruses are a type of virus that was first discovered in 1975 using electron microscopes following an outbreak of diarrhea in humans. In addition to humans, astroviruses have now been isolated from numerous mammalian animal species (and are classified as genus ''Mamastrovirus'') and from avian species such as ducks, chickens, and turkey poults (classified as genus ''Avastrovirus''). Astroviruses are 28–35 nm diameter, icosahedral viruses that have a characteristic five- or six-pointed star-like surface structure when viewed by electron microscopy. Along with the Picornaviridae and the Caliciviridae, the Astroviridae comprise a third family of nonenveloped viruses whose genome is composed of plus-sense, single-stranded RNA. Astrovirus has a non-segmented, single stranded, positive sense RNA genome within a non-enveloped icosahedral capsid. Human astroviruses have been shown in numerous studies to be an important cause of gastroenteritis in young children worldwide. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrograph
A micrograph or photomicrograph is a photograph or digital image taken through a microscope or similar device to show a magnified image of an object. This is opposed to a macrograph or photomacrograph, an image which is also taken on a microscope but is only slightly magnified, usually less than 10 times. Micrography is the practice or art of using microscopes to make photographs. A micrograph contains extensive details of microstructure. A wealth of information can be obtained from a simple micrograph like behavior of the material under different conditions, the phases found in the system, failure analysis, grain size estimation, elemental analysis and so on. Micrographs are widely used in all fields of microscopy. Types Photomicrograph A light micrograph or photomicrograph is a micrograph prepared using an optical microscope, a process referred to as ''photomicroscopy''. At a basic level, photomicroscopy may be performed simply by connecting a camera to a microscope, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrobrachium Rosenbergii
''Macrobrachium rosenbergii'', also known as the giant river prawn or giant freshwater prawn, is a commercially important species of Palaemonidae, palaemonid freshwater prawn. It is found throughout the tropical and subtropical areas of the Indo-Pacific region, from India to Southeast Asia and Northern Australia. The giant freshwater prawn has also been introduced to parts of Africa, Thailand, China, Japan, New Zealand, the Americas, and the Caribbean. It is one of the biggest freshwater prawns in the world, and is widely Aquaculture, cultivated in several countries for food. While ''M. rosenbergii'' is considered a freshwater species, the larval stage of the animal depends on brackish water. Once the individual shrimp has grown beyond the planktonic stage and becomes a juvenile, it lives entirely in fresh water. It is also known as the Malaysian prawn, freshwater scampi (India), or cherabin (Australia). Locally, it is known as ''golda chingri'' ( bn, গলদা চিংড ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
