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Betacoronaviruses
''Betacoronavirus'' (β-CoVs or Beta-CoVs) is one of four genera (''Alpha''-, ''Beta-'', '' Gamma-'', and '' Delta-'') of coronaviruses. Member viruses are enveloped, positive-strand RNA viruses that infect mammals, including humans. The natural reservoir for betacoronaviruses are bats and rodents. Rodents are the reservoir for the subgenus ''Embecovirus'', while bats are the reservoir for the other subgenera. The coronavirus genera are each composed of varying viral lineages with the betacoronavirus genus containing four such lineages: A, B, C, D. In older literature, this genus is also known as "group 2 coronaviruses". The genus is in the subfamily ''Orthocoronavirinae'' in the family ''Coronaviridae'', of the order ''Nidovirales''. The betacoronaviruses of the greatest clinical importance concerning humans are OC43 and HKU1 (which can cause the common cold) of lineage A, SARS-CoV-1 and SARS-CoV-2 (the causes of SARS and COVID-19 respectively) of lineage B, and MERS-CoV ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Embecovirus
''Embecovirus'' is a subgenus of coronaviruses in the genus '' Betacoronavirus''. The viruses in this subgenus, unlike other coronaviruses, have a hemagglutinin esterase (HE) gene. The viruses in the subgenus were previously known as group 2a coronaviruses. Taxonomy The subgenus contains the following species, listed by scientific name and followed by the exemplar virus of the species: * '' Betacoronavirus gravedinis'', Human coronavirus OC43 * ''Betacoronavirus hongkongense'', Human coronavirus HKU1 * ''Betacoronavirus muris'', Murine hepatitis virus * ''Betacoronavirus myodae'', Myodes rufocanus vole coronavirus 2/JL2014 * ''Betacoronavirus ratti'', Betacoronavirus HKU24 Structure The viruses of this subgenus, like other coronaviruses, have a lipid bilayer envelope in which the membrane (M), envelope (E) and spike (S) structural proteins are anchored. Unlike other coronaviruses, viruses in this subgenus also have an additional shorter spike-like structural protein c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Murine Coronavirus
Murine coronavirus (M-CoV) is a virus in the genus ''Betacoronavirus'' that infects mice. Belonging to the subgenus ''Embecovirus'', murine coronavirus strains are :wikt:enterotropic, enterotropic or polytropic. Enterotropic strains include mouse hepatitis virus (MHV) strains D, Y, RI, and DVIM, whereas polytropic strains, such as JHM and A59, primarily cause hepatitis, enteritis, and encephalitis. Murine coronavirus is an important pathogen in the laboratory mouse and the laboratory rat. It is the most studied coronavirus in animals other than humans, and has been used as an animal disease model for many virological and clinical studies. Types Murine hepatitis virus Murine coronavirus was first discovered in 1949. The researchers isolated the virus from the brain, spinal cord, liver, lung, spleen, and kidney of a rat with symptoms of encephalitis and severe myelin injury, and gave it the strain name mouse hepatitis virus (MHV)-JHM. MHV is now the most studied coronavirus in anim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Human Coronavirus HKU1
Human coronavirus HKU1 (HCoV-HKU1, ''Betacoronavirus hongkonense'') is a species of coronavirus in humans and animals. It causes an upper respiratory disease with symptoms of the common cold, but can advance to pneumonia and bronchiolitis. It was first discovered in January 2004 from one man in Hong Kong. Subsequent research revealed it has global distribution and earlier genesis. The virus is an Viral envelope, enveloped, Sense (molecular biology), positive-sense, RNA, single-stranded RNA virus which enters its host cell by binding to the N-Acetylneuraminic acid, N-acetyl-9-O-acetylneuraminic acid receptor. It has the Hemagglutinin esterase (HE) gene, which distinguishes it as a member of the genus ''Betacoronavirus'' and subgenus ''Embecovirus''. History HCoV-HKU1 was first detected in January 2004, in a 71-year-old man who was hospitalized due to acute respiratory distress syndrome and radiographically confirmed bilateral pneumonia. The man had recently returned to Hong Kong f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Human Coronavirus OC43
Human coronavirus OC43 (HCoV-OC43) is a member of the species ''Betacoronavirus 1, Betacoronavirus gravedinis'', which infects humans and cattle. The infecting coronavirus is an Viral envelope, enveloped, Sense (molecular biology), positive-sense, RNA, single-stranded RNA virus that enters its host cell by binding to the N-Acetylneuraminic acid, N-acetyl-9-O-acetylneuraminic acid receptor. OC43 is one of Coronavirus#Infection in humans, seven coronaviruses known to infect humans. It is one of the viruses responsible for the common cold and may have been responsible for the 1889–1890 pandemic. It has, like other coronaviruses from genus ''Betacoronavirus,'' subgenus ''Embecovirus'', an additional shorter spike protein called hemagglutinin esterase, hemagglutinin-esterase (HE). ]. Genetic and antigenic analyses reveal significant similarities between HCoV-OC43 and bovine coronavirus (BCoV), suggesting a zoonotic transmission event from cattle to humans. Molecular analysis estimate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
SARS-CoV-2 Beta Variant
The Beta variant (B.1.351) was a variant of SARS-CoV-2, the virus that causes COVID-19. One of several SARS-CoV-2 variants initially believed to be of particular importance, it was first detected in the Nelson Mandela Bay metropolitan area of the Eastern Cape province of South Africa in October 2020, which was reported by the country's health department on 18 December 2020. Phylogeographic analysis suggests this variant emerged in the Nelson Mandela Bay area in July or August 2020. The World Health Organization labelled the variant as Beta variant, not to replace the scientific name but as a name for the public to commonly refer to. The WHO considers it to be a variant of concern no longer in circulation. Names The variant is also known as the ''South African variant''. Mutations File:SARS-CoV-2 Beta variant.svg, Amino acid mutations of SARS-CoV-2 Beta variant plotted on a genome map of SARS-CoV-2 with a focus on Spike. There are three mutations of particular inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Letter (alphabet)
In a writing system, a letter is a grapheme that generally corresponds to a phoneme—the smallest functional unit of speech—though there is rarely total one-to-one correspondence between the two. An alphabet is a writing system that uses letters. Definition and usage A letter is a type of grapheme, the smallest functional unit within a writing system. Letters are graphemes that broadly correspond to phonemes, the smallest functional units of sound in speech. Similarly to how phonemes are combined to form spoken words, letters may be combined to form written words. A single phoneme may also be represented by multiple letters in sequence, collectively called a ''multigraph (orthography), multigraph''. Multigraphs include ''digraphs'' of two letters (e.g. English ''ch'', ''sh'', ''th''), and ''trigraphs'' of three letters (e.g. English ''tch''). The same letterform may be used in different alphabets while representing different phonemic categories. The Latin H, Greek eta , an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Beta
Beta (, ; uppercase , lowercase , or cursive ; or ) is the second letter of the Greek alphabet. In the system of Greek numerals, it has a value of 2. In Ancient Greek, beta represented the voiced bilabial plosive . In Modern Greek, it represents the voiced bilabial fricative while in borrowed words is instead commonly transcribed as μπ. Letters that arose from beta include the Roman letter and the Cyrillic letters and . Name Like the names of most other Greek letters, the name of beta was adopted from the acrophonic name of the corresponding letter in Phoenician, which was the common Semitic word ('house', compare and ). In Greek, the name was , pronounced in Ancient Greek. It is spelled in modern monotonic orthography and pronounced . History The letter beta was derived from the Phoenician letter beth . The letter Β had the largest number of highly divergent local forms. Besides the standard form (either rounded or pointed, ), there were forms as varied ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ancient Greek
Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek Dark Ages, Dark Ages (), the Archaic Greece, Archaic or Homeric Greek, Homeric period (), and the Classical Greece, Classical period (). Ancient Greek was the language of Homer and of fifth-century Athens, fifth-century Athenian historians, playwrights, and Ancient Greek philosophy, philosophers. It has contributed many words to English vocabulary and has been a standard subject of study in educational institutions of the Western world since the Renaissance. This article primarily contains information about the Homeric Greek, Epic and Classical periods of the language, which are the best-attested periods and considered most typical of Ancient Greek. From the Hellenistic period (), Ancient Greek was followed by Koine Greek, which is regar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
MERS
Middle East respiratory syndrome (MERS) is a viral respiratory infection caused by '' Middle East respiratory syndrome–related coronavirus'' (MERS-CoV). Symptoms may range from none, to mild, to severe depending on age and risk level. Typical symptoms include fever, cough, diarrhea, and shortness of breath. The disease is typically more severe in those with other health problems. The first case was identified in June 2012 by Egyptian physician Ali Mohamed Zaki at the Dr. Soliman Fakeeh Hospital in Jeddah, Saudi Arabia, and most cases have occurred in the Arabian Peninsula. Over 2,600 cases have been reported as of January 2021, including 45 cases in the year 2020. About 35% of those who are diagnosed with the disease die from it. Larger outbreaks have occurred in South Korea in 2015 and in Saudi Arabia in 2018. MERS-CoV is a virus in the coronavirus family believed to be originally from bats. However, humans are typically infected from camels, either during direct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
MERS-CoV
Middle East respiratory syndrome–related coronavirus (MERS-CoV, ''Betacoronavirus cameli'') or EMC/2012 ( HCoV-EMC/2012), is the virus that causes Middle East respiratory syndrome (MERS). It is a species of coronavirus which infects humans, bats, and camels. The infecting virus is an enveloped, positive-sense, single-stranded RNA virus which enters its host cell by binding to the DPP4 receptor. The species is a member of the genus ''Betacoronavirus'' and subgenus '' Merbecovirus''. Initially called simply novel coronavirus or nCoV, with the provisional names 2012 novel coronavirus (2012-nCoV) and human coronavirus 2012 (HCoV-12 or hCoV-12), it was first reported in June 2012 after genome sequencing of a virus isolated from sputum samples from a person who fell ill in a 2012 outbreak of a new flu-like respiratory illness. By July 2015, MERS-CoV cases had been reported in over 21 countries, in Europe, North America and Asia as well as the Middle East. MERS-CoV is one of seve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
COVID-19
Coronavirus disease 2019 (COVID-19) is a contagious disease caused by the coronavirus SARS-CoV-2. In January 2020, the disease spread worldwide, resulting in the COVID-19 pandemic. The symptoms of COVID‑19 can vary but often include fever, fatigue, cough, breathing difficulties, anosmia, loss of smell, and ageusia, loss of taste. Symptoms may begin one to fourteen days incubation period, after exposure to the virus. At least a third of people who are infected asymptomatic, do not develop noticeable symptoms. Of those who develop symptoms noticeable enough to be classified as patients, most (81%) develop mild to moderate symptoms (up to mild pneumonia), while 14% develop severe symptoms (dyspnea, hypoxia (medical), hypoxia, or more than 50% lung involvement on imaging), and 5% develop critical symptoms (respiratory failure, shock (circulatory), shock, or organ dysfunction, multiorgan dysfunction). Older people have a higher risk of developing severe symptoms. Some complicati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
SARS
Severe acute respiratory syndrome (SARS) is a viral respiratory disease of zoonotic origin caused by the virus SARS-CoV-1, the first identified strain of the SARS-related coronavirus. The first known cases occurred in November 2002, and the syndrome caused the 2002–2004 SARS outbreak. In 2004, Xue Wu Zhang and Yee Leng Yap found that the Spike 2 (S2) protein of SARS is structurally similar to HIV-1 gp41 subunit, suggesting an analogous membrane fusion mechanism between the two. In the 2010s, Chinese scientists traced the virus through the intermediary of Asian palm civets to cave-dwelling horseshoe bats in Xiyang Yi Ethnic Township, Yunnan.The locality was referred to be "a cave in Kunming" in earlier sources because the Xiyang Yi Ethnic Township is administratively part of Kunming, though 70 km apart. Xiyang was identified on * For an earlier interview of the researchers about the locality of the caves, see: SARS was a relatively rare disease; at the end of the ep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
