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Biomedical subjects

R Reece

Publications and source records attributed to R Reece.

25 records · Page 2Linked to original sources
PubMedDate not supplied

Pathogenicity of Australian strains of avian infectious bronchitis virus.

The pathogenicity of 25 strains of infectious bronchitis virus (IBV) isolated in Australia between 1961 and 1994 was compared in white leghorn specific pathogen-free chicks. Twelve strains were nephropathogenic and 10 respiratory, the other three being of mixed pathogenicity. The IBV strains identified as nephropathogenic induced clinical nephritis, gross and histological kidney lesions, and mortality of 5-90%. According to the severity of these features, the nephropathogenic strains could be further subdivided into strains of high, moderate or low pathogenicity. The three strains of mixed pathogenicity induced tracheitis, mild clinical nephritis and kidney lesions but no mortality. The 10 respiratory strains caused histological lesions in the trachea but not in the kidney, and did not induce clinical nephritis or mortality. Of 12 IBV strains isolated between 1961 and 1976, nine were nephropathogenic, inducing mortality of 15-90%. In contrast, of 13 strains isolated between 1981 and 1994, only three were nephropathogenic, inducing mortality of 5-37%, whereas nine were respiratory. Seven of these nine strains, unlike other respiratory strains, failed completely to replicate in the kidney. The results indicated a change in the prevalent IBV strains from highly nephropathogenic (1960s to 1970s) to respiratory (1980s to early 1990s); moreover, the late 1980s saw the emergence of respiratory strains with altered tissue tropism.

Animals↗
PubMedDate not supplied

Susceptibility of three genetic lines of chicks to infection with a nephropathogenic T strain of avian infectious bronchitis virus.

Mortality rates were compared in three genetic lines of specific pathogen-free chicks inoculated with one of two doses of a nephropathogenic strain of avian infectious bronchitis (IB) virus. The mortality rates were influenced primarily by the chick strain, but also by age and dose of virus. Chicks of the inbred S line were highly susceptible. After inoculation with a low dose of virus at 2 and 4 weeks of age, mortality was 90 and 45%, respectively. Chicks of the HWL non-inbred line were also susceptible, with mortality rates after inoculation at 2 and 4 weeks of age of 70 and 25%, respectively. Chicks of the inbred W line were resistant and non-significant mortality of 10% occurred only in 2-week-old chicks inoculated with a high dose of virus. Viral distribution in tissues of susceptible S and resistant W chicks did not differ, and virus was present in the trachea, lung and kidney of chicks from both lines throughout the acute phase (between days 3 and 7) of infection. Viral titres in the trachea and kidney in susceptible S chicks were slightly but not significantly higher than in the other chicks during the acute phase of infection. Histopathological assessment indicated an earlier onset of a regenerative phase in the trachea of W chicks than in S chicks. S chicks, in contrast to W chicks, showed no signs of renal regeneration. Additionally, the kidneys of S chicks differed from those of W chicks in showing more severe nephritis, more tubular necrosis and less heterophil infiltration and lymphocytic response throughout the acute phase of infection. The results indicate that chicken lines may differ greatly in their susceptibility to fatal IB nephritis and that resistance is likely to be under the control of immune responses to viral infection.

Age Factors↗
PubMedDate not supplied

Group treatment of sexual dysfunction in gay men.

Three different formats for treating gay men with sexual dysfunctions are described, with emphasis on group therapy for men who are without partners. Clients present with general sexual anxieties, lack of sexual desire, secondary erectile dysfunctions, and difficulties with ejaculatory control, both rapid and inhibited. The process of selecting a program, and in particular the factors to consider when deciding if a client should work with a lover, with a partner surrogate or in a group format, are discussed. Primary procedures of sex therapy in each of these formats are described. Some trends in the frequencies of presenting complaints are noted, as well as possible reasons for reported differences between homosexual and heterosexual men. Other special considerations for working with gay men in sex therapy are discussed. Results of a self-report survey of change, administered 6 weeks and again 6 months following the end of 5 different 10-week sex therapy groups, are reported.

Adult↗