PubMed Health⌕ Search

Biomedical subjects

T Barrett

Publications and source records attributed to T Barrett.

At least 19 recordsLinked to original sources
PubMed1992

Molecular and serological studies on the recent seal virus epizootics in Europe and Siberia.

The virus epizootics which occurred in seals in both Europe and Siberia during 1987/1988 were caused by two different morbilliviruses, referred to as phocid distemper virus (PDV) 1 and 2, respectively. Molecular and serological studies have shown that the European virus is quite distinct from canine distemper virus (CDV), its closest relative in the morbillivirus group. Analysis of tissues obtained from infected seals from a wide geographical distribution over Northern Europe showed that the infectious agent (PDV 1) was identical in all cases. Nucleotide sequence analysis of one of the virus genes suggested that this virus has evolved away from CDV over a long time period and is most probably an enzootic virus of marine mammals. In contrast, the virus (PDV 2) which caused the deaths of many Siberian seals was indistinguishable, both serologically and at the molecular level, from CDV and must have originated from a land source.

Animals↗
PubMed1992

Canine distemper virus ISCOMs induce protection in harbour seals (Phoca vitulina) against phocid distemper but still allow subsequent infection with phocid distemper virus-1.

A candidate canine distemper virus (CDV) ISCOM vaccine has been shown to be effective in protecting harbour seals (Phoca vitulina) from phocid distemper in 1988. However, of the 35 harbour seals receiving this vaccine upon admission to a seal rehabilitation and research centre (Pieterburen, The Netherlands) in 1989, six developed mild inflammatory symptoms of the respiratory tract. Phocid distemper virus-1 (PDV-1) could be isolated from three of these animals. This indicates that the vaccine affords protection from phocid distemper, but may still allow PDV-1 infection of the respiratory tract. Contacts with non-vaccinated seals should then be prevented until no more virus is excreted. It is speculated that this PDV-1 infection of the respiratory tract in CDV-ISCOM vaccinated seals is followed by a lifelong immunity.

Animals↗
PubMed1992

Round table on morbilliviruses in marine mammals.

Since 1988 morbilliviruses have been increasingly recognized and held responsible for mass mortality amongst harbour seals (Phoca vitulina) and other seal species. Virus isolations and characterization proved that morbilliviruses from seals in Northwest Europe were genetically distinct from other known members of this group including canine distemper virus (CDV), rinderpest virus, peste des petits ruminants virus and measles virus. An epidemic in Baikal seals in 1987 was apparently caused by a morbillivirus closely related to CDV so that two morbilliviruses have now been identified in two geographically distant seal populations, with only the group of isolates from Northwest Europe forming a new member of the genus morbillivirus: phocid distemper virus (PDV). Because of distemper-like disease, the Baikal seal morbillivirus was tentatively named PDV-2 in spite of its possible identity with CDV. The appearance of morbilliviruses in the Mediterranean Sea causing high mortality amongst dolphins should further increase the research activities on protection strategies for endangered species of marine mammals.

Animals↗
PubMed1992

Arthritis outpatients: disability, pain and alcohol use.

There is a small body of literature describing investigations into the relationships between pain and disabling conditions and alcohol consumption. Of these few studies, most have concluded that pain and disability are positively associated with alcohol consumption, though these particular studies have not been methodologically rigorous. Arthritis is the most prevalent of the disabling conditions, and one of the major symptoms of arthritis is pain. Several factors associated with the disease are thought to make arthritis sufferers particularly vulnerable to the use of alcohol for its mind-altering and analgesic properties. In the present study, conducted in 1987, a sample of 154 Perth arthritic outpatients were interviewed to investigate the relationship between pain, disability and alcohol consumption. Results showed that pain and disability scores were very weak predictors of volume of weekly alcohol consumption for males, but the relationship was in a negative direction. Results from a previous study were confirmed in the finding that being an ex-drinker was a predictor of a higher disability score for females. Fewer patients were drinkers than in the population at large and fewer drank at the level of the highest consumption category. However, the proportions of male and female patients drinking above NHMRC low risk levels were the same as the general population (age-standardised comparison). Most who considered themselves current drinkers said that alcohol did not help their pain, stiffness or weakness. Various possible explanations are offered for these results and recommendations for future research are presented.

Adolescent↗
PubMed1992

Recognition and treatment of surgical wound infections.

1. Tissue traumatized by surgery heals in a three-phase sequential process: a defensive response to the injury, reconstruction of the site, and maturation (closing) of the wound. 2. Not all patients undergoing surgery are at equal risk for infection. The anatomic location of the surgery, the seeding of the surgical site with the patient's own normal flora, the OR environment and personnel, and the presence of a foreign body left in place after closure all contribute to the risk of infection. 3. The treatment of postoperative infection can be divided into the physical aspects of wound care and the appropriate use of antimicrobial agents.

Humans↗
PubMed1991

Deduced amino acid sequence of the fusion glycoprotein of turkey rhinotracheitis virus has greater identity with that of human respiratory syncytial virus, a pneumovirus, than that of paramyxoviruses and morbilliviruses.

The sequence of the fusion (F) glycoprotein of turkey rhinotracheitis virus (TRTV) has been deduced from cDNA clones derived from oligo(dT)-selected infected cell RNA. The protein consists of 538 amino acids, the F2 and F1 subunits containing 102 (including the F2-F1 connecting peptide RRRR) and 436 residues, respectively. Each subunit has one potential N-linked glycosylation site. The protein has 38 to 39% amino acid identity with the F protein of respiratory syncytial virus (Pneumovirus genus) but only about half that with members of the other two genera (Paramyxovirus and Morbillivirus) in the Paramyxoviridae family. This is the first sequence evidence to support the view that TRTV is a pneumovirus, the first avian member of the genus to be described.

Amino Acid Sequence↗
PubMed1991

Detection of phocid distemper virus RNA in seal tissues using slot hybridization and the polymerase chain reaction amplification assay: genetic evidence that the virus is distinct from canine distemper virus.

Slot hybridization and the polymerase chain reaction (PCR) after reverse transcription (RT) were used to detect RNA extracted from tissues of seals after naturally occurring disease and experimental infection with phocid distemper virus (PDV). A phosphoprotein (P) gene-specific cDNA served as a probe for both slot hybridization and the identification of PCR-generated fragments by Southern blotting. As primers for the PCR assay PDV P gene-derived oligonucleotides were used. Hybridization, PCR and partial nucleic acid sequence analysis clearly demonstrated that PDV is a distinct virus (most closely related to canine distemper virus) within the morbillivirus group. PCR, when combined with Southern blot hybridization, was clearly superior to slot hybridization and more sensitive than cell culture isolation and immunofluorescence assays for the detection of virus in tissues. Considerable amounts of viral RNA could be demonstrated in the lungs and spleens. In experimentally infected animals a large quantity of virus-specific RNA was additionally found in colon samples. Using RT-PCR in combination with Southern blotting. PDV could be demonstrated in buffy coat cells using a simple and fast cell lysis procedure.

Animals↗
PubMed1990

The role of the 5' nontranslated regions of the fusion protein mRNAs of canine distemper virus and rinderpest virus.

The mRNAs which code for the fusion proteins of the morbilliviruses (measles virus, canine distemper virus, and rinderpest virus) have unusually long 5' untranslated regions (UTRs) which are GC-rich and are capable of folding into extensive secondary structures. In measles virus the first AUG codons in the fusion (F) protein mRNA are in close proximity at nucleotide positions 574 and 583 and protein translation is initiated at the second position. In the canine distemper virus (CDV) and rinderpest virus (RPV) F gene transcripts the analogous initiation codons are preceded by several other AUG codons many nucleotides upstream either in the same reading frame or at the beginning of other short open reading frames. We have studied the effect of deleting these upstream regions on the production of the fusion proteins of both CDV and RPV from cDNA constructs. Within the cells the presence of these regions enhances the production of the F protein while, in contrast, the production of the authentic F protein from in vitro translations using RNA transcripts is inhibited by these sequences.

Animals↗
PubMed1990

Observations on the pathogenicity for sheep and goats and the transmissibility of the strain of virus isolated during the rinderpest outbreak in Sri Lanka in 1987.

The pathogenicity for sheep and goats of the virus strain that caused acute rinderpest in cattle and domestic buffalo in Sri Lanka after an interval of over 40 years has been examined. The results show that it can cause overt clinical disease in goats, but only mild or unapparent infection in sheep. The disease was transmitted from infected sheep to in-contact susceptible sheep and calves.

Animals↗
PubMed1990

The epidemiology of peste des petits ruminants in the Sultanate of Oman.

Virological and serological evidence was obtained to show that peste des petits ruminants virus was widely distributed in Omani sheep and goats. There was no evidence for the concomitant presence of rinderpest virus in these species. Two virus isolates were classified as peste des petits ruminants virus on the basis of their pathogenicity in experimental animals and their specific hybridisation with nucleic acid probes. However, neutralisation tests and polyacrylamide gel analysis of their nucleocapsid proteins showed that they were not identical to the highly conserved African strains of this virus.

Age Factors↗
PubMed1990

Characterisation of the European seal morbillivirus.

The ELISA test originally developed for the detection of serum antibodies to rinderpest virus has been shown to detect cross-reacting antibodies in sera of diseased common and grey seals. Analysis of sera collected from various seal populations is in progress to establish the correlation between different morbillivirus neutralisation tests, ELISA tests and the disease status of the animals. RNA purified from post-mortem tissues removed from diseased seals has been analysed by hybridisation with cloned cDNAs made to various genes of canine distemper, peste des petits ruminants, rinderpest and measles viruses. This study has confirmed the presence of RNA sequences characteristic of a morbillivirus, but shown that the virus is not identical with any known morbillivirus. Work is in progress to determine the nucleotide sequences of clones carrying inserts homologous to morbillivirus genes isolated from cDNA made on a template of infected seal tissue RNA.

Animals↗
PubMed1990

Effect of exercise level on ventilatory adaptation to respirator use.

The effect of exercise on the adaptation to an air-purifying respirator type load (dead space + inspiratory resistance) was studied in a group of 13 volunteers with a rapidly incremental exercise protocol. The difference between loaded and unloaded breathing at each exercise level was determined for each subject for a series of parameters describing the ventilatory work to overcome the respirator load pattern of breathing and metabolic work. Linear regression and t tests determined the average effect of the respirator load and the extent to which this effect was affected by the level of exercise. The inspiratory time and duty cycle were increased by the load, and exercise did not significantly affect the magnitude of this adaptation. High exercise did, however, increase the magnitude of the effect of the respiratory load on ventilatory work. These findings suggest that constraints to respiratory pattern adjustment, which may decrease respirator tolerance, occur at high exercise levels.

Adaptation, Physiological↗
PubMed1990

Detection of phocine distemper virus using the polymerase chain reaction.

During the fatal seal epizootics in the North and Baltic Seas in summer 1988 a virus was isolated which was shown to be the causal agent. It was subsequently classified as morbillivirus by neutralization assays, reaction with monoclonal antibodies and nucleic acid hybridization studies. The virus (tentatively called Phocine Distemper Virus, PDV) is difficult to grow in culture making rapid diagnosis difficult. We have used the Polymerase Chain Reaction (PCR) as an alternative and fast method to detect the presence of virus-specific nucleic acid and we describe here the amplification of cell culture derived PDV RNA in a "one-tube" reaction using heterologous (Rinderpest Virus cDNA derived) F gene primers. The resulting 370 bp DNA fragment was shown to be morbillivirus derived by Southern blot hybridization using cloned RPV F gene as probe.

Animals↗