Recombinant vaccinia virus expressing PrM and E glycoproteins of louping ill virus: induction of partial homologous and heterologous protection in mice.

Recombinant vaccinia viruses expressing either the premembrane/truncated envelope (PrM/TrE) or truncated envelope (TrE) protein of louping ill virus were constructed. Both constructs expressed authentic E proteins as determined by their size and antigenic reactivity with a panel of monoclonal antibodies. The deletion of the C-terminal hydrophobic domain of the envelope glycoprotein resulted in the secretion of E protein into the supernatant culture medium.

Towards a new generation of flavivirus vaccines.

Flavivirus diseases have caused great public health concern for over three centuries, with diseases like yellow fever, dengue, Japanese encephalitis and tick-borne encephalitis causing thousands of deaths. Although yellow fever epidemics can be brought under control by the use of vaccine or mosquito-control measures, there have been many examples of its re-emergence as an epidemic disease. Similarly, the use of vaccines or arthropod-control measures have failed to prevent the spread of other flaviviruses such as Japanese encephalitis virus.

A single chain antibody fragment expressed in bacteria neutralizes tick-borne flaviviruses.

A recombinant single chain antibody fragment (scFv) that identifies a neutralizing epitope on the envelope glycoprotein of louping iII (LI) and tick-borne encephalitis (TBE) virus has been developed using a bacteriophage expression system. The mRNA was extracted from a cloned hybridoma cell culture that produces a mouse monoclonal antibody (MAb 4.2) known to map to amino acids 308-311 of LI and TBE virus, corresponding to domain B on the proposed two-dimensional model of the tick-borne encephalitis virus envelope protein.

Tick-borne flavivirus NS1 gene: identification of conserved peptides and antigenic analysis of recombinant louping ill virus NS1 protein.

The nucleotide sequence of the NS1 gene of louping ill (LI) virus has been determined. The sequence shows a high degree of homology with other members of the tick-borne serocomplex of flaviviruses and a lower homology with the mosquito-borne flaviviruses. Alignment of the deduced NS1 amino acid sequences with all tick-borne flavivirus NS1 sequences, identified four peptide regions which were conserved for all tick-borne flaviviruses, but were variable amongst mosquito-borne flaviviruses.

Analysis of the structural protein gene sequence shows Kyasanur Forest disease virus as a distinct member in the tick-borne encephalitis virus serocomplex.

Kyasanur Forest disease (KFD) virus is a highly pathogenic member of the family Flaviviridae producing a haemorrhagic disease in infected human beings. Despite this high pathogenicity and potential epidemiological importance, there have been relatively few detailed antigenic or molecular studies on KFD virus. The nucleotide sequences of the genes encoding the structural proteins of the virus have now been determined.

Nucleotide and deduced amino acid sequence of the envelope gene of the Vasilchenko strain of TBE virus; comparison with other flaviviruses.

A strain of tick-borne encephalitis virus known as Vasilchenko (Vs) exhibits relatively low virulence characteristics in monkeys, Syrian hamsters and humans. The gene encoding the envelope glycoprotein of this virus was cloned and sequenced. Alignment of the sequence with those of other known tick-borne flaviviruses and identification of the recognised amino acid genetic marker EHLPTA confirmed its identity as a member of the TBE complex.

Improving the dynamic response of neural network controllers using velocity reference feedback.

A neural network controller designed solely based on the desired response of the dynamics to realize a maximum acceptable steady-state error may not be the best one in terms of the transient responses. It may have an excessive overshoot and larger risetime. Similarly, a controller having a very good transient response may not have the desired steady-state characteristics.

Sequencing and antigenic studies of a Norwegian virus isolated from encephalomyelitic sheep confirm the existence of louping ill virus outside Great Britain and Ireland.

We have carried out an antigenic analysis and nucleotide sequence comparison of the envelope glycoprotein of recognized louping ill virus strains isolated from Scotland with that of a Norwegian virus known to cause encephalomyelitis in sheep. Monoclonal antibodies with defined specificity for the louping ill virus envelope glycoprotein failed to distinguish between the Norwegian virus and prototype louping ill virus in indirect immunofluorescence, haemagglutination inhibition and neutralization tests. Nucleotide sequencing of the envelope glycoprotein and alignment of the deduced amino acid sequence with other known sequences revealed that the Norwegian virus closely resembles (> 95% identity for nucleotide and > 98% identity for amino acid sequences) louping ill virus.

Nucleotide sequence of the envelope glycoprotein of Negishi virus shows very close homology to louping ill virus.

Negishi virus, a member of the family Flaviviridae, was originally isolated in Japan, during an outbreak of Japanese encephalitis. Antigenically, however, Negishi virus resembles the tick-borne rather than the mosquito-borne flaviviruses. Monoclonal antibodies that bind louping ill virus showed a close antigenic relationship between louping ill and Negishi virus.

Heterologous resistance to superinfection by louping ill virus persistently infected cell cultures.

Louping ill virus, a tick-borne arbovirus readily established a persistent infection in porcine kidney (PS) cells after initially inducing minor cytopathic changes. Nucleotide sequence analysis of the envelope glycoprotein of the viral RNA recovered from the persistently infected cells showed no changes as compared with the virus used to establish persistent infections. More than 80 per cent of the cells contained virus specific antigen when analysed by indirect immunofluorescence microscopy.

Lesions and immune responses produced in hamsters and guinea pigs inoculated with some strains of leptospira.

Pathogenic lesions and immune responses in hamsters and guinea pigs produced by three leptospiral serovars, viz. autumnalis, grippotyphosa, and pomona, and their pool were experimentally studied. Hepatic lesions precede renal localisation.

Effect of pancuronium on intraocular pressure changes induced by succinylcholine.

The study was undertaken to evaluate the influence of pretreatment with a small dose of pancuronium on intraocular pressure changes associated with administration of succinylcholine and tracheal intubation. Thirty patients divided into control and study groups were anaesthetized with sodium thiopentone (3-5 mg mg.kg-1) and intubation with the aid of succinylcholine (1 mg.