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Biomedical subjects

D A Tyrrell

Publications and source records attributed to D A Tyrrell.

At least 145 records · Page 8Linked to original sources

Dengue viruses.

Explore the source record for details and available documents.

Blood↗

Influenza vaccines.

Inactivated influenza vaccines can now be made from purified haemagglutinin and neuraminidase. Although they have not been fully tested in the field they probably produce as good an immunity as whole virus vaccines and fewer reactions. They could be used against a new serotype in the face of a pandemic. Revaccination with killed vaccine may be effective, but one careful study in a school during the drifting of the H3N2 showed that it was not effective there overall. Live influenza vaccines have been made that were safe and effective and agreed methods are available for their evaluation. When the new generation of live vaccine strains are available, that have been more fully characterized genetically and functionally, they should be evaluated in substantial long-term trials.

Antibodies, Viral↗

Isolation of rhinoviruses and coronaviruses from 38 colds in adults.

Nasal washings were collected from 27 normal adults during 38 naturally acquired colds. The washings were exhaustively tested using tissue cultures, organ cultures and electron microscopy. Washings yielding no identifiable agent were inoculated into human volunteers, and further specimens obtained from the latter were examined by the same techniques in vitro. Viruses were identified in association with 25 of the original 38 colds (65.7%). Fifteen were rhinoviruses (39.5%), seven coronaviruses (18.4%), two were para-influenza viruses, and one was influenza virus. Use of organ cultures and of volunteers significantly increased the isolation rate. No agent was cultivated from the remaining 13 specimens, although tests in volunteers showed that cold-producing agents were present in five of them (13%). Three specimens gave doubtful results in volunteers, and five others, all collected within a period of six weeks in December and January, apparently contained no infectious agent.

Adult↗

Skin reactions to interferon inoculations are reduced but not abolished by purification.

The skin reactions to partially-purified fibroblast-derived (HulFN-beta) and leucocyte-derived (HulFN-alpha) interferons and to HulFN-alpha of increasing purity were studied in normal volunteers. Reactions consisted of an immediate flare followed by a dense well-circumscribed erythema maximal at 4-8 hours. HulFN-beta caused significantly larger reactions than HulFN-alpha of approximately the same purity. Immediate flare reactions occurred even to the most pure preparation tested but the late reactions were significantly reduced. Experiments suggested that the early reactions to impure HulFN-alpha were in part mediated by local histamine release and late reactions in part by local prostaglandin synthesis. This suggests that interferon itself may not be the cause of general symptoms during a virus illness.

Chromatography, Gel↗

Approaches to the control of respiratory virus diseases.

Viruses of various biological types are known to cause a wide range of acute respiratory infections, ranging from mild colds and catarrh to severe bronchiolitis and pneumonia. Bacteria also cause respiratory diseases including serious conditions such as otitis media and pneumonia. The whole situation is complex and to understand the epidemiology we also need to consider nutrition, environment, climate, and chronic diseases. Acute respiratory viral diseases are very common in all areas of the world and contribute to morbidity and probably to mortality. There are no antiviral drugs or vaccines which would be generally useful. It ought to be possible to reduce the effects of these diseases by improving the standard of general management of cases. This would involve careful nursing, administration of appropriate antibiotics, and referral of severe cases to a properly staffed and equipped hospital. Further research is needed to develop ways of doing this and to evaluate the results.

Acute Disease↗

Impaired polymorphonuclear leucocyte chemotaxis after influenza virus infection.

Polymorphonuclear leucocyte function was assessed in 13 patients with influenza by measuring phagocytosis of staphylococci and chemotaxis. Significant impairment of chemotaxis was shown. Subsequeuntly polymorph chemotaxis was found to be impaired in a group of volunteers infected with virus recombinants of A/New Jersey/8/76 but not in volunteers infected with a virus recombinant of A/Victoria/3/75. These results accord well with the in vitro effects of certain influenza viruses on polymorph function and suggest that interference with polymorph function may predispose to bacterial pneumonia after clinical influenza.

Chemotaxis, Leukocyte↗

Possible virus in schizophrenia and some neurological disorders.

Cerebrospinal fluid from 13 of 38 patients with schizophrenia had a cytopathic effect in cultures of MRC5 cells. The cytopathic agent passed a 100 nm but not a 50 nm filter and was unaffected by heat at 56 degrees C for 30 min, treatment with chloroform, or the presence in cultures of bromodeoxyuridine. The agent could not be propagated serially in a satisfactory manner but its properties were those of a virus. A similar cytopathic effect was induced by cerebrospinal fluid from 8 of 11 patients with serious or chronic nervous system disease but only 1 of 25 patients with surgical or general medical conditions.

Adolescent↗

Characteristics of patients with schizophrenia or neurological disorder and virus-like agent in cerebrospinal fluid.

A virus-like agent (V.L.A.) with a cytopathic effect on cultured cells was found in the cerebrospinal fluid of 18 of 47 patients with schizophrenia, of whom 10 had nuclear schizophrenic symptoms. In most patients with V.L.A., blood and C.S.F. protein concentrations were normal. Patients with and without V.L.A. had similar clinical characteristics but serum IgA levels were higher in those with V.L.A. V.L.A. was also detected in the C.S.F. of 8 of 11 patients with serious or chronic neurological disease (Huntington's chorea, multiple sclerosis, and unexplained alterations of consciousness).

Acute Disease↗

Clones of cells from a human embryo lung: their growth and susceptibility to respiratory viruses.

Colonies of cells were obtained from human fetal lung tissue and exposed to recently isolated respiratory viruses. There was a considerable variation in the number of rounded cells found in different colonies exposed to rhinovirus types 2 and 9 (RV2 and 9), human coronavirus 229E (HCV), adenovirus type 3 (Ad3) and respiratory syncytial virus (RSV). Smaller colonies had more rounded cells than larger colonies. Clones were established from 9 out of 11 colonies. They varied in their rate of growth and the pattern formed on a plastic surface. They varied also in their virus susceptibility particularly to "difficult" rhinoviruses such as RV9 and SF1340. One cell clone (HL1/77 Clone 8), was highly susceptible to all these viruses. All cultures were more sensitive to RSV when maintained in F12K medium than in MEM, whereas there was no difference for rhinoviruses. Influenza A and B and parainfluenza 3 viruses sometimes produced cytopathic effect, and always produced haemadsorption, but unlike the previous strains could not be passed serially and presumably produced little infectious virus. All clones were rather insusceptible to Ad3; but the virus could be passed, whereas coxsackie virus B3 produced no CPE. Substantial yields of coronavirus and rhinovirus were obtained in gelatin sponge cultures. Two "very difficult" respiratory viruses which had just been adapted to tissue culture; namely, HS rhinovirus and JK coronavirus grew in 7 of 9 and in 6 of 9 clones respectively.

Adenoviruses, Human↗