culture material to 2 formalin reduced infectivity by 99.9 after 5 minutes, and completely after ... cell culture material to 0.025 formalin for 60 minutes caused only a negligible reduction in infectivity ... infectivity. ref name Frerichs1990 The virus does not lose infectivity when exposed in cell culture ... more details
In the diagnostic laboratory virus infections are confirmed by several methods that include Growth of the virus in a cell culture from a specimen taken from the patient. Detection of virus specific antibodies in the blood. Detection of virus antigens Detection of virus nucleic acids Observation of virus particles by electron microscopy . Hemagglutination assay Cell culture main Viral culture When growing virus in a cell culture , the cells affected with virus will evolve morphologic changes, often specific for the type of virus involved. Antibody detection When the adaptive immune system of a vertebrate encounters a virus, it produces specific antibodies which bind to the virus and render it non infectious. This is called humoral immunity . Two types of antibodies are important. The first called IgM is highly effective at neutralizing viruses but is only produced by the cells of the immune system for a few weeks. The second, called, IgG is produced indefinitely. The presence of IgM in the blood of the host is used to test for acute infection, whereas IgG indicates an infection sometime in the past. ref Greer S, Alexander GJ. Viral serology and detection. Baillieres Clin Gastroenterol. 1995 Dec 9 4 689 721 ref Both types of antibodies are measured when tests for Immunity medical immunity are carried out. ref Laurence JC. Hepatitis A and B immunizations of individuals infected with humanimmunodeficiency virus.Am J Med. 2005 Oct 118 Suppl 10A 75S 83S. ref Antigen detection Detection of virus antigens can be done by ELISA in tissues and fluids. Other techniques are immunofluorescence immunoperoxidase Hemagglutination assay Main Hemagglutination assay Many viruses attach to molecules present on the surface of red blood cells. A consequence of this is that at certain concentrations a viral suspension may bind together agglutinate the red blood cells thus preventing them from settling out of suspension. Usefully, agglutination is rarely linked to infectivity, attenuated vi ... more details
Infobox protein family Symbol Hema HEFG Name Hemagglutinin domain of haemagglutinin esterase fusion glycoprotein image PDB 1flc EBI.jpg width caption x ray structure of the haemagglutinin esterase fusion glycoprotein of influenza c virus Pfam PF02710 Pfam clan InterPro IPR003860 SMART PROSITE MEROPS SCOP 1flc TCDB OPM family OPM protein CAZy CDD In molecular biology, haemagglutinin esterase fusion glycoprotein HEF is a multi functional protein embedded in the viral envelope of several viruses , including influenza C virus , Coronavirus coronaviruses and torovirus toroviruses . ref name pmid16575523 cite journal author de Groot RJ title Structure, function and evolution of the hemagglutinin esterase proteins of corona and toroviruses journal Glycoconj. J. volume 23 issue 1 2 pages 59 72 year 2006 month February pmid 16575523 doi 10.1007 s10719 006 5438 8 url ref ref name pmid9817207 cite journal author Rosenthal PB, Zhang X, Formanowski F, Fitz W, Wong CH, Meier Ewert H, Skehel JJ, Wiley DC title Structure of the haemagglutinin esterase fusion glycoprotein of influenza C virus journal Nature volume 396 issue 6706 pages 92 6 year 1998 month November pmid 9817207 doi 10.1038 23974 url ref HEF is required for infectivity , and functions to recognise the host cell surface receptor , to fuse the virus viral and host cell membranes , and to destroy the receptor upon host Cell biology cell infection . The haemagglutinin region of HEF is responsible for receptor recognition and membrane fusion, and bears a strong resemblance to the sialic acid binding haemagglutinin found in influenza A and Influenza B B viruses, except that it Molecular binding bind s 9 O acetylsialic acid. The esterase region of HEF is responsible for the destruction of the receptor, an action that is carried out by neuraminidase in influenza A and B viruses. The esterase protein domain domain is similar in secondary structure structure to Streptomyces scabies esterase, and to acetylhydrolase, thioesterase ... more details
, destroy prion infectivity, but treatments that destroy nucleic acids, like UV radiation , do not destroy prion infectivity. The prion protein is known as PrP and is a cell surface glycophosphatidylinositol ... more details
and infectivity journal Mol. Microbiol. volume 58 issue 1 pages 46 60 year 2005 month October pmid ... are involved in parasite differentiation and infectivity journal Mol. Microbiol. volume 58 issue ... more details
of HIV and SIV infectivity by blockade of alpha glucosidase activity journal Virology volume 181 ... Interference with HIV induced syncytium formation and viral infectivity by inhibitors of trimming ... more details
Heyden N, Dedera D title Inhibition of HIV and SIV infectivity by blockade of alpha glucosidase ..., Neefjes JJ, Tersmette M, et al. title Interference with HIV induced syncytium formation and viral infectivity ... more details
unreferenced date August 2007 expert subject Medicine date February 2010 Orphan date February 2009 The virino is a hypothesis hypothetical infection infectious particle theorized to be the cause of scrapie and other degenerative disease s of the central nervous system it is thought to consist of nucleic acid in a protective coat of host cell protein s. The major problem regarding scrapie and other transmissible encephalopathy spongiform encephalopathies TSEs is to determine the nature of the transmission agent. Origin of the Virino Concept The virino was described partially to protect the central dogma of molecular biology , which was threatened by the existence of a series of degenerative neurological TSE diseases including Kuru disease kuru , Creutzfeldt Jakob disease CJD , scrapie in sheep, and Bovine spongiform encephalopathy BSE in cows. The central dogma states that nucleic acid s act as the information carriers, and thus that DNA & RNA make proteins. Proteins alone cannot make DNA. However, studies searching for the transmission agent of scrapie and other TSEs have failed to culture bacteria , and tests attacking nucleic acids strands have little effect on the infectivity of TSE solutions. These failures largely rule out a virus as the infective agent. Experiments using electron beams designed to disrupt large molecule s have been performed to investigate the size of the agent show that it is very small much smaller than the smallest known virus . The virino also has the benefit of explaining the traits of TSEs which resemble nucleic acids for example, their occurrence in strains, which positively indicates that the TSE agent is information carrying, and not merely a toxin . History of Description In 1971 Dickinson, AG and Meikle, VM provided a hypothesis for the replication of the scrapie agent. This hypothesis was based on the discovery of a single autosomal gene controlling the scrapie incubation period in mouse mice and on observations about strains of th ... more details
cleanup date November 2009 Taxobox virus group iv familia Caliciviridae genus Vesivirus species Subphylum Vertebrata synonyms Calicivirus The genus vesivirus is in the Caliciviridae family of viruses . It includes feline calicivirus ,San Miguel sealion virus, and vesicular exanthema of swine virus . ref Farles. http medical dictionary.thefreedictionary.com Vesivirus The Free Dictionary. Accessed 02 Mar 2010. ref Virus Virion Properties Morphology biology Morphology Virions consist of a capsid . Virus capsid is not enveloped, and are round with icosahedral symmetry . The isometric capsid has a diameter of 35 39 Nanometer nm . Capsids appear round to Virus Structure hexagonal in outline. The capsid surface structure reveals a regular pattern with distinctive features. The capsomer arrangement is clearly visible. Capsid with 32 cup shaped depressions. Physical chemistry and Physical property The molecular mass Mr of virions is 15 x 106. Virions have a Buoyancy Density buoyant density in Caesium chloride CsCl of 1.33 1.41 g cm sup 3 sup . The density gradient Biology density gradient of virions in Potassium Tartrate Glycerol is 1.29 g cm sup 3 sup . The sedimentation coefficient is 170 187 svedberg s sub 20,w sub , of the other s peak at 160 170 svedberg s sub 20,w sub . Under in vitro conditions virions are inactivated in acid environment of pH 3 5. Virions are not stable at raised temperature in presence of high concentration of Mg . Virions are sensitive to treatment with trypsin in some Strain biology Microbiology and virology strains , not sensitive to treatment with mild detergents, or ether , or chloroform . The infectivity is enhanced after treatment with trypsin in some strains . Nucleic acid The genome is not Virus Genome segmented and contains a single molecule of linear Sense molecular biology Positive sense positive sense , single stranded RNA . Minor species of non genomic nucleic acid are some times also found in virions. The complete genome is 7700 nucle ... more details
Taxobox virus group iv familia Caliciviridae genus Vesivirus species Subphylum Vertebrata synonyms Calicivirus Virus Virion Properties Morphology biology Morphology Virions consist of a capsid . Virus capsid is not enveloped, round with icosahedral symmetry . The isometric capsid has a diameter of 35 39 nm. Capsids appear round to Virus Structure hexagonal in outline. The capsid surface structure reveals a regular pattern with distinctive features. The capsomer arrangement is clearly visible. Capsid with 32 cup shaped depressions. Physical chemistry and Physical property The molecular mass Mr of virions is 15 x 10 sup 6 sup . Virions have a Buoyancy Density buoyant density in Caesium chloride CsCl of 1.33 1.36 g cm sup 3 sup . The density gradient Biology density gradient of virions in Potassium Tartrate Glycerol is 1.29 g cm sup 3 sup . The sedimentation coefficient is 170 187 svedberg s sub 20,w sub of the other s are peak 160 170 svedberg s sub 20,w sub believed to consist of defective interfering particles . Under in vitro conditions virions are inactivated in acid environment of pH 4.5 7 stable in alkaline environment of pH 7 10.5. Virions are not stable at raised temperature in presence of high concentration of Mg . Virions are sensitive to treatment with trypsin in some Strain biology Microbiology and virology strains , not sensitive to treatment with mild detergents, or ether , or chloroform . The infectivity is enhanced after treatment with trypsin in some strains . Nucleic acid The genome is not Virus Genome segmented and contains a single molecule of linear Sense molecular biology Positive sense positive sense , ss RNA virus RNA . Minor species of non genomic nucleic acid are some times also found in virions. The encapsidated nucleic acid is mainly of genomic origin, but virions may also contain subgenomic RNA. The complete genome is 7450 nucleotides long. The genome has a guanine cytosine content of 49.3 50.1 . The 5 end of the genome has a usually ... more details
Multiple issues orphan February 2012 COI June 2011 primarysources June 2011 The term kodecyte is used to describe cells with detectable FSL constructs, ref name Heathcote2010 ref name Henry2009 ref name Oliver2011a ref name Oliver2011b and in concert, the term kodevirion pronounced co da virion , is used to describe virion s with detectable Function Spacer Lipid FSL constructs. ref name Hadac2011 ref name Blake2011 The method for labeling virions with FSL constructs is simple, noncovalent bonding non covalent and only involves Incubator culture incubation of the virion with the FSL construct in Saline water saline for a few hours nothing further is required. ref name Hadac2011 ref name Blake2011 The FSL construct will spontaneously, stably and quantitatively incorporate into the viral membrane virion membrane . Virions have been labelled with fluorescent FSL FLRO4 and Iodine 125 radioactive iodine FSL 125I . FSL FLRO4 could be shown to label virions in a dose dependent manner and could be visualized by flow cytometry either directly, or indirectly if the virion had bound to the cell or fused with the cell membrane. ref name Blake2011 FSLs do not appear to significantly affect the virions infectivity or their ability to bind target cells, probably because they integrate into the membrane without exposing the virion to chemical agents or covalent modification Citation needed date June 2011 . References reflist refs ref name Heathcote2010 cite journal author Heathcote D, Carroll T, Wang JJ, Flower R, Rodionov I, Tuzikov A, Bovin N, Henry S. title Novel antibody screening cells, MUT Mur kodecytes, created by attaching peptides onto erythrocytes. journal Transfusion doi 10.1111 j.1537 2995.2009.02480.x volume 50 issue 3 pages 635 641 year 2010 ref ref name Henry2009 cite journal author Henry S title Modification of red blood cells for laboratory quality control use. journal Current Opinion in Hematology 2009 doi 10.1097 MOH.0b013e328331257e volume 16 issue 6 pages 467 47 ... more details
viral infectivity . However, when tested in cell culture with micromolar concentrations, it was found that biliverdin and bilirubin reduced infectivity by blocking viral entry into cells. Results ... and their effects on HIV 1 viral maturation and infectivity in vitro journal The Biochemical ... more details
factor able to restrict replication of HIV 1 lacking the viral accessory protein Viral infectivity ... enzyme confers resistance to HIV 1 virion infectivity factor induced depletion journal PNAS ... tRNA3Lys priming, thereby negatively affecting viral ssDNA production and virus infectivity. ref name ... factor of HIV 1 replication and infectivity. However, Vif counteracts this antiretroviral factor, enabling ... more details
italic title Taxobox color lightgrey name Spiroplasma regnum Bacterium Bacteria phylum Tenericutes classis Mollicutes ordo Entomoplasmatales familia Spiroplasmataceae genus Spiroplasma Spiroplasma is a genus of Mollicutes , a group of small bacteria without cell wall s. Spiroplasma shares the simple metabolism , parasitic lifestyle, fried egg colony morphology and small genome of other Mollicutes , but has a distinctive helical morphology, unlike Mycoplasma . It has a spiral shape and moves in a corkscrew motion. Most spiroplasmas are found either in the gut or hemolymph of insects, or in the phloem of plants. Spiroplasmas are Growth medium fastidious organisms, which require a rich culture medium. Typically they grow well at 30 C, but not at 37 C. A few species, notably Spiroplasma mirum , grow well at 37 C human body temperature , and cause cataract s and neurological damage in suckling mice. The best studied species of spiroplasmas are Spiroplasma citri , the causative agent of Citrus Stuborn Disease , and Spiroplasma kunkelii , the causative agent of Corn Stunt Disease . Image Spiro.jpg right thumb 250px Corn Stunt Spiroplasma in phloem cells. Thick section 0.4 micrometers observed in a TEM. Magnified 75,000X. There is some disputed evidence for the role of spiroplasmas in the etiology of Transmissible spongiform encephalopathy Transmissible Spongiform Encephalopathies TSEs , due primarily to the work of Dr. Bastian, summarized below. Other researchers, such as Leach et al. 1983 have failed to replicate this work, while the prion model for TSEs has gained very wide acceptance. The most recent work of Alexeeva et al. 2006 appears to refute the role of spiroplasmas in the best small animal scrapie model hamsters . Bastian et al. 2007 have responded to this challenge with the isolation of a spiroplasma species from scrapie infected tissue, grown it in cell free culture, and demonstrated its infectivity in ruminants. According to Frank O. Bastian, MD blockquote spir ... more details
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