|
Viral Hepatitis
Viral hepatitis is liver inflammation due to a viral infection. It may present in acute form as a recent infection with relatively rapid onset, or in chronic form. The most common causes of viral hepatitis are the five unrelated hepatotropic viruses hepatitis A, B, C, D, and E. Other viruses can also cause liver inflammation, including cytomegalovirus, Epstein–Barr virus, and yellow fever. There also have been scores of recorded cases of viral hepatitis caused by herpes simplex virus. Mode Of Transmission Viral hepatitis is either transmitted through contaminated food or water (A, E) or via blood and body fluids (B, C). The viruses transmitted through water and food are mostly self-limited, resulting in acute illness with full resolution. The blood borne viruses (B, C) can cause both acute and chronic liver disease and can be transmitted from mother to child during birth, through contact with body fluids during sex, unsafe injections and through unscreened blood transf ... [...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] |
Yellow Fever
Yellow fever is a viral disease of typically short duration. In most cases, symptoms include fever, chills, loss of appetite, nausea, muscle pains – particularly in the back – and headaches. Symptoms typically improve within five days. In about 15% of people, within a day of improving the fever comes back, abdominal pain occurs, and liver damage begins causing yellow skin. If this occurs, the risk of bleeding and kidney problems is increased. The disease is caused by the yellow fever virus and is spread by the bite of an infected mosquito. It infects humans, other primates, and several types of mosquitoes. In cities, it is spread primarily by ''Aedes aegypti'', a type of mosquito found throughout the tropics and subtropics. The virus is an RNA virus of the genus ''Flavivirus''. The disease may be difficult to tell apart from other illnesses, especially in the early stages. To confirm a suspected case, blood-sample testing with polymerase chain reaction is required. A saf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
(−)ssRNA Virus
Baltimore classification is a system used to classify viruses based on their manner of messenger RNA (mRNA) synthesis. By organizing viruses based on their manner of mRNA production, it is possible to study viruses that behave similarly as a distinct group. Seven Baltimore groups are described that take into consideration whether the viral genome is made of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA), whether the genome is single- or double-stranded, and whether the sense of a single-stranded RNA genome is positive or negative. Baltimore classification also closely corresponds to the manner of replicating the genome, so Baltimore classification is useful for grouping viruses together for both transcription and replication. Certain subjects pertaining to viruses are associated with multiple, specific Baltimore groups, such as specific forms of translation of mRNA and the host range of different types of viruses. Structural characteristics such as the shape of the viral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DsDNA-RT Virus
Baltimore classification is a system used to classify viruses based on their manner of messenger RNA (mRNA) synthesis. By organizing viruses based on their manner of mRNA production, it is possible to study viruses that behave similarly as a distinct group. Seven Baltimore groups are described that take into consideration whether the viral genome is made of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA), whether the genome is single- or double-stranded, and whether the sense of a single-stranded RNA genome is positive or negative. Baltimore classification also closely corresponds to the manner of replicating the genome, so Baltimore classification is useful for grouping viruses together for both transcription and replication. Certain subjects pertaining to viruses are associated with multiple, specific Baltimore groups, such as specific forms of translation of mRNA and the host range of different types of viruses. Structural characteristics such as the shape of the viral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
(+)ssRNA
Baltimore classification is a system used to classify viruses based on their manner of messenger RNA (mRNA) synthesis. By organizing viruses based on their manner of mRNA production, it is possible to study viruses that behave similarly as a distinct group. Seven Baltimore groups are described that take into consideration whether the viral genome is made of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA), whether the genome is single- or double-stranded, and whether the sense of a single-stranded RNA genome is positive or negative. Baltimore classification also closely corresponds to the manner of replicating the genome, so Baltimore classification is useful for grouping viruses together for both transcription and replication. Certain subjects pertaining to viruses are associated with multiple, specific Baltimore groups, such as specific forms of translation of mRNA and the host range of different types of viruses. Structural characteristics such as the shape of the viral ... [...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] |
Incertae Sedis
' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty at specific taxonomic levels is indicated by ' (of uncertain family), ' (of uncertain suborder), ' (of uncertain order) and similar terms. Examples *The fossil plant '' Paradinandra suecica'' could not be assigned to any family, but was placed ''incertae sedis'' within the order Ericales when described in 2001. * The fossil ''Gluteus minimus'', described in 1975, could not be assigned to any known animal phylum. The genus is therefore ''incertae sedis'' within the kingdom Animalia. * While it was unclear to which order the New World vultures (family Cathartidae) should be assigned, they were placed in Aves ''incertae sedis''. It was later agreed to place them in a separate order, Cathartiformes. * Bocage's longbill, ''Motacilla bocagii' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flaviviridae
''Flaviviridae'' is a family of enveloped positive-strand RNA viruses which mainly infect mammals and birds. They are primarily spread through arthropod vectors (mainly ticks and mosquitoes). The family gets its name from the yellow fever virus; ''flavus'' is Latin for "yellow", and yellow fever in turn was named because of its propensity to cause jaundice in victims. There are 89 species in the family divided among four genera. Diseases associated with the group include: hepatitis (hepaciviruses), hemorrhagic syndromes, fatal mucosal disease (pestiviruses), hemorrhagic fever, encephalitis, and the birth defect microcephaly (flaviviruses). Structure Virus particles are enveloped and spherical with icosahedral-like geometries that have pseudo T=3 symmetry. They are about 40–60 nm in diameter. Genome Members of the family ''Flaviviridae'' have monopartite, linear, single-stranded RNA genomes of positive polarity, and 9.6 to 12.3 kilobase in total length. The 5'-termini of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepadnaviridae
''Hepadnaviridae'' is a family of viruses. Humans, apes, and birds serve as natural hosts. There are currently 18 species in this family, divided among 5 genera. Its best-known member is hepatitis B virus. Diseases associated with this family include: liver infections, such as hepatitis, hepatocellular carcinomas (chronic infections), and cirrhosis. It is the sole accepted family in the order ''Blubervirales''. Taxonomy The following genera are recognized: * ''Avihepadnavirus'' * ''Orthohepadnavirus'' * '' Herpetohepadnavirus'' * '' Metahepadnavirus'' * '' Parahepadnavirus'' History and discovery Although liver diseases transmissible among human populations were identified early in the history of medicine, the first known hepatitis with a viral etiological agent was Hepatitis A, in the picornaviridae family. Hepatitis B Virus (HBV) was identified as an infection distinct from Hepatitis A through its contamination of measles, mumps, and yellow fever vaccines in the 1930s and 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picornaviridae
Picornaviruses are a group of related nonenveloped RNA viruses which infect vertebrates including fish, mammals, and birds. They are viruses that represent a large family of small, positive-sense, single-stranded RNA viruses with a 30 nm icosahedral capsid. The viruses in this family can cause a range of diseases including the common cold, poliomyelitis, meningitis, hepatitis, and paralysis. Picornaviruses constitute the family ''Picornaviridae'', order ''Picornavirales'', and realm '' Riboviria''. There are 158 species in this family, assigned to 68 genera. Notable examples are genera ''Enterovirus'' (including ''Rhinovirus'' and ''Poliovirus''), ''Aphthovirus'', ''Cardiovirus'', and ''Hepatovirus''. Etymology The name "picornavirus" has a dual etymology. Firstly, the name derives from ''picorna''- which is an acronym for "''p''oliovirus, ''i''nsensitivity to ether, ''c''oxsackievirus, ''o''rphan virus, ''r''hinovirus, and ribo''n''ucleic ''a''cid". Secondly, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatitis E Virus
The hepatitis E virus (HEV) is the causative agent of hepatitis E. It is of the species ''Orthohepevirus A.'' Globally, approximately 939 million corresponding to 1 in 8 individuals have ever experienced HEV infection. About 15–110 million individuals have recent or ongoing HEV infection. The virus particle was first seen in 1983, but was only molecularly cloned in 1989. Genome and proteome ''Orthohepevirus A'' can be classified into eight different genotypes from different geographical regions: genotype 1 (Asia), genotype 2 (Africa and Mexico), genotype 3 (Europe and North America), genotype 4 (Asia); genotypes 5 and 6 have been detected in Asian wild boar and genotypes 7 and 8 in camels.Schlauder, G. G. & Mushahwar, I. K. (2001) Genetic heterogeneity of hepatitis E virus. J Med Virol 65, 282–92 The viral genome is a single strand of positive-sense RNA that is about 7200 bases in length. The three open-reading frames (ORF1, ORF2 and ORF3) encode for three proteins (O1, O2, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatitis D Virus
Hepatitis D is a type of viral hepatitis caused by the hepatitis delta virus (HDV). HDV is one of five known hepatitis viruses: hepatitis A, A, hepatitis B, B, hepatitis C, C, D, and hepatitis E, E. HDV is considered to be a Satellite (biology), satellite (a type of subviral agent) because it can propagate only in the presence of the hepatitis B, hepatitis B virus (HBV). Transmission of HDV can occur either via simultaneous infection with HBV (coinfection) or superimposed on chronic hepatitis B or hepatitis B carrier state (superinfection). HDV infecting a person with chronic hepatitis B (superinfection) is considered the most serious type of viral hepatitis due to its severity of complications. These complications include a greater likelihood of experiencing liver failure in acute infections and a rapid progression to liver cirrhosis, with an increased risk of developing liver cancer in chronic infections. In combination with hepatitis B virus, hepatitis D has the highest fatality ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
