Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In a study on Fischer rats, all animals infected with Japanese encephalitis virus (JEV) before the age of 13 days died, but animals infected after the age of 14 days did not die, confirming the age-dependent resistance to JEV infection in the rat brain. A study of the kinetics of JEV infection in the developing rat brain disclosed that JEV antigen disappeared in a particular pattern, i.e., from the deeper layers to the upper layers of the motor cortex, which paralleled neuronal maturation in the cortex. Fifteen-day-old rats, which were resistant to JEV infection, received intracerebral transplants of neurons taken from 19-day embryos. When these animals were infected with JEV after transplantation, viral antigen was detected only in the embryonal neurons soon after transplantation. Thus, it can be concluded that the susceptibility to JEV infection in the rat brain is closely associated with neuronal immaturity.
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PMID:Japanese encephalitis virus neurotropism is dependent on the degree of neuronal maturity. 198 78

It is generally accepted that, the younger an animal is, the more susceptible it is to Japanese encephalitis virus (JEV) infection. A time-kinetic study of JEV antigen in the developing rat brain after infection disclosed that in the motor cortex, neurons were diffusely infected with JEV until the age of 5 days. However, on exposure from the 6th to 7th day, only the neurons of the upper layers were infected; those of the deeper layers remained uninfected. On the 8th day, the infection was limited to the superficial neurons, and from the 9th day onward, no neurons were infected. Since neuronal maturation in the motor cortex begins in the deeper layers and extends to the upper layers, it seems that JEV targets immature neurons. Fifteen-day-old rats, which were resistant to JEV infection, received intracerebral transplants of neurons taken from 19th-day embryos. When these animals were infected with JEV at 3 days after transplantation, viral antigen was detected only in the transplanted neurons; the host neurons were negative. However, when animals were infected with JEV at 9 days after transplantation, neither host neurons nor donor neurons became infected. This showed that JEV attacked embryonal neurons only early after transplantation into young-adult brains. JEV infectivity limited to the immature neurons was also confirmed by in vitro explant culture experiments. It can be concluded from these experiments that the susceptibility to JEV infection in the rat brain is closely associated with neuronal immaturity.
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PMID:[Dependency of Japanese encephalitis virus neurotropism on neuronal immaturity of rat cerebral cortex]. 216 65

In the central nervous system, the Japanese encephalitis virus can replicate only in neurons. The mechanism of the type of neurotropism was analyzed. The susceptibility to Japanese encephalitis virus infection in the rat brain was closely associated with neuronal immaturity. The initial specific binding of the virus to cells is one of the reasons for neurotropism of the Japanese encephalitis virus. The treatment of Japanese encephalitis virus infection with the neutralizing monoclonal antibody against the E protein did not inhibit the virus from binding to the cell surfaces, but strongly inhibited Japanese encephalitis virus-induced cell fusion and internalization of the virus into the host cells. One of the genome regions responsible for neuropathogenesis of the Japanese encephalitis virus was located on the E protein-coding region. The 138th amino acid of the E protein was important for neuropathogenesis expression of the Japanese encephalitis virus. The cell fusion activity of the E protein was closely correlated with neuropathogenesis of the virus.
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PMID:Neuropathogenesis of Japanese encephalitis virus. 1249 Nov 61