Viruses prions

The search for life in the cosmos requires a generalised, universal definition of life. This must take into account the properties of systems ranging from viruses, prions, denucleated cells or endospores to life in a test tube, computer viruses or even to robots which are capable of self-replication. 

Suggested Alternatives for Differential Diagnosis Bartonellosis, brucellosis, other causes of encephalitis, coxsackieviruses, cryptococcosis, cysticercosis, cytomegalovirus, histoplasmosis, legionellosis, leptospirosis, listeria, lyme disease, malaria, rabies, tuberculosis, mumps, stroke, metabolic encephalopathy, Reye syndrome, Bartonella infection, Naegleria infection, Ebstein-Barr virus, prion disease, toxic ingestions, and AIDS. 

Prions are responsible for the so-ealled slow virus diseases, a distinet group of unusual neurologieal disorders. They are believed to be markedly resistant to inactivation by many ehemieal and physical agents but because they have not been purified, it is at present diffieult to state whether this is an intrinsic property of prions or whether it results fkm the proteetive effect of host tissue present. Certainly very high coneentrations of a bioeide aeting for long periods may be necessary to produee inactivation. 

Beekes, M., Lemmer, K., Thomzig, A., Joncic, M., Tintelnot, K., and Mielke, M. (2010). Fast, broad-range disinfection of bacteria, fungi, viruses and prions. /. Gen. Virol. 91, 580-589. 

One of the most obvious benefits of plants is the potential for production scale up, leading to the production of virtually limitless amounts of recombinant antibody at minimal cost Plants are easy to grow, and unlike bacteria or animal cells their cultivation is straightforward and does not require specialist media, equipment or toxic chemicals. It has been estimated that plantibodies could be produced at a yield of 10-20 kg per acre at a fraction of the cost associated with production in mammalian cells [2,18] The use of plants also avoids many of the potential safety issues associated with other expression systems, such as contaminating mammalian viruses or prions, as well as ethical considerations involving the use of animals. 

In addition, the regulatory authorities are concerned about contamination with viruses and prions, such as the causative agent of bovine spongiform encephalopathy (BSE), which could be present in mammalian cell cultures. It is necessary to... 

The prion diseases are a closely related group of neuro-degenerative conditions which affect both humans and animals. They have previously been described as the subacute spongiform encephalopathies, slow virus diseases and transmissible dementias, and include scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle, and the human prion diseases, Creutzfeldt-Jakob disease (CJD), Gerstmann-Straussler-Scheinker disease (GSS), fatal familial insomnia (FFI) and kuru. Prion diseases are... 

To meet the infectivity requirement in the definition of a prion, the abnormal form of the protein must be transmissible to other cells and organisms of the same species. In yeast and filamentous fungi, infectious agents such as viruses and plasmids are naturally transmitted by cytoplasmic mixing during mating or heterokaryon formation (Wickner, 2001). 

Abstract. The hybrid cell lines, which we have obtained, can be widely used in veterinary virology and biotechnology for preparing vaccines, test-systems for viruses. Any strains of hybrid cells are producing the biological active proteins (enzymes and others). We have obtained hybrid cell lines (PO-TKxCO, PO-TKxHO), which are sensitive to prion protein, and also hybrid culture with P-cells of the pancreas of rabbit. 

GPRT- defective cells appear in population. Using the method of the selective pressure by 5-BDU and 8-Ag, the mutant cultures of cells, defective by the indicated enzymes, are obtained. The intraspecific and interspecific hybrid cultures of cells are firstly obtained in the laboratory of the cellular biotechnology, A4H (SPEV TK- x lymphocytes of horse) and others. Hybrid cultures possess the unique properties. They are the ability to grow in the monolayer and in suspension, the high sensitiveness to the viruses. Hybrid cultures PO-TK-KHLO, PO-TK-KHSO are sensible to the agent scrappy, what allows using them for the study of diseases, caused by prions. 

Prions, viruses, bacteria, fungi, parasites (pneumonia, meningitis, gastroenteritis) Neoplastic (pathology from tumors, cancer)... 

The abnormal deposits found in the brains of CJD victims consist of an abnormal isoform of PrP. Prion protein is normally found in cells. Detailed structural studies show that normal cellular PrP (PrP ) is a soluble protein whose conformation is rich in a-helices with very little P-sheet. The PrP protein extracted from the brains of CJD victims (i.e., PrP ) is identical in primary amino acid sequence to the normal PrP (PrP ). However, PrP has a much greater content of P-sheet conformation with little a-helical structure. Thus PrP is neurotoxic because of its three-dimensional structure. When the prion protein is predominantly in an a-helical conformation it is nontoxic when the prion protein is predominantly in a P-sheet conformation, it kills neurons. The prion protein is thus made neurotoxic not by its amino acid composition but by its conformation. This concept is both fascinating and terrifying. Prion diseases are transmissible thus prions are infectious agents. However, prions are not like bacteria or viruses, or other infectious microbes—they are simply protein molecules. Prions are not microbes with cell membranes and nucleic acids they are not living things. Indeed, prions are not even infectious molecules, they are infectious molecular shapes. 

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