PubMed Health⌕ Search

Biomedical subjects

L E Rogers

Publications and source records attributed to L E Rogers.

18 recordsLinked to original sources
PubMed2006

Infectivity and persistence of an outbreak strain of Salmonella enterica serotype Typhimurium DT160 for house sparrows (Passer domesticus) in New Zealand.

AIM: To examine the infective dose, incubation period and disease progression of an isolate of Salmonella enterica serotype Typhimurium definitive type 160 (DT160) originating from a naturally-infected house sparrow (Passer domesticus) during an outbreak of the disease in New Zealand. METHODS: Thirty-six house sparrows captured from the wild and free of Salmonella spp were divided into six groups of six birds, housed individually, and inoculated orally with phosphate buffered saline (PBS) or 10(1), 10(2), 10(3), 10(5), 2 x 10(8) colony forming units (cfu) of the outbreak strain of S. Typhimurium DT160. The birds were observed for 10 days for clinical signs and/or mortality, and faecal samples were collected to determine excretion of S. Typhimurium. The birds were euthanised 11 days post-inoculation (p.i.) and a wide range of tissue samples were collected for histopathological examination, and culture and typing of Salmonella spp. Macro-restriction profiling by pulsed-field gel electrophoresis (PFGE) using XbaI was performed for the epidemiological typing of S. Typhimurium DT160 isolates. RESULTS: Mortality in house sparrows inoculated with S. Typhimurium DT160 was dose-dependent, and 2/6 birds inoculated with 10(5) cfu and all six birds inoculated with 2 x 10(8) cfu died during the study. Infected sparrows displayed few clinical signs, apart from diarrhoea and/or polyuria, fluffed plumage, and sitting on the floor of the cage. Faecal excretion of DT160 occurred briefly in two birds inoculated with 10(2) cfu and four birds inoculated with 10(3) cfu, on most days in five birds inoculated with 10(5) cfu, and continuously in six birds inoculated with 2 x 10(8) cfu. DT160 was isolated from the livers of three birds which received 10(3) cfu, five birds dosed with 10(5) cfu, and all six birds given 2 x 10(8) cfu. Following necropsy, histopathological lesions similar to those seen in the natural disease were observed in the liver or spleen of three birds which received 10(3) cfu, and all birds dosed with > or =10(5) cfu. CONCLUSION: The results indicate that an isolate of S. Typhimurium DT60 originating from house sparrows in New Zealand is pathogenic to these birds and that the response is dose dependent. The persistence and excretion of the pathogen may last for at least 10 days. This confirms that sparrows infected with DT160 could be a source of infection to humans and other in-contact animals.

Animals↗
PubMed2002

An epidemic of salmonellosis caused by Salmonella Typhimurium DT160 in wild birds and humans in New Zealand.

AIM: This study reports an outbreak of salmonellosis due to S. Typhimurium DT160 which caused extensive mortality in wild birds and enteric disease in humans in New Zealand during the winter and spring months of the year 2000. METHODS: Necropsies were performed and microbiological examinations undertaken on wild birds from populations in which mass mortality was reported, and on captive indigenous birds which died suddenly during the winter and spring of 2000. Affected tissues were examined histologically and isolates of S. Typhimurium were phage typed and examined using pulsedfield gel electrophoresis (PFGE). Isolates of S. Typhimurium obtained from cases of human enteric disease which occurred during these months were phage typed, examined using PFGE and compared with the bird isolates. RESULTS: Central and northern areas of the South Island and the southern North Island were worst affected with die-offs of several hundreds of sparrows and other birds reported in rural areas. Mortalities reached a peak in winter (July-August) 2000 and decreased to small numbers during the spring and early summer. The birds usually died of an acute septicaemia with multifocal necrotising lesions in the liver and spleen. Human cases throughout the country increased gradually over the same period. Isolates from birds, livestock and humans examined using PFGE were indistinguishable from one another. CONCLUSION: This strain of Salmonellahas emerged as a major cause of septicaemia in wild birds in New Zealand. Because of the close association between house sparrows (Passer domesticus) and humans, the organism also poses a serious zoonotic risk. The possibility that the infection may spread to involve indigenous species needs investigation.

Journal Article↗
PubMed1985

Methods for analyzing marital conflict discourse: implications of a systems approach.

A large number of studies of family and marital conflictual interaction purport to describe relational processes, yet close examination reveals a scarcity of process analyses. Many studies are interactional or systemic in name only. Three basic criteria are proposed as necessary for the development of a systems methodology: observable, sequential, system-level behavioral descriptions. A methodological review of the literature reveals that the first criterion yielded the most abundant set of methodologies. Application of the second criterion resulted in a much smaller number, which after the third criterion dwindled to a mere handful. This review does not focus on the substantive results of these investigations but rather on the research criteria, strategies, and issues that need to be addressed if process-oriented measures are to be developed for the study of interpersonal systems.

Conflict, Psychological↗
PubMed1975

Hereditary orotic aciduria: results of a screening survey.

Urine from 1,358 mentally retarded subjects was screened for the presence of elevated concentrations of orotic acid and orotidine. This survey was conducted in search of occult variants of hereditary orotic aciduria which might be associated with mental retardation. Although no homozygous variants were detected, 9 subjects with persistently abnormal urinary screening tests were discovered. Assays of erythrocyte orotidylate decarboxylase and phosphoribosyltransferase enzymes showed deficient activities for 2 of these subjects typically found in red cells of persons heterozygous for hereditary orotic aciduria. The same studies were conducted on urine and blood samples from the families of the affected subjects, and additional family members were also found to be affected. Detection of two unrelated heterozygotes among so small a screened population suggests, as previously noted, a higher frequency of the abnormal gene than that indicated by the extreme rarity of the homozygous condition. This study demonstrates the usefulness of the urinary screening test mass surveys and indicates the need for further study of the prevalence of the mutant gene.

Adult↗
PubMedDate not supplied

Osteoporosis: impact on the elderly societal concerns, and the role of radiology.

Osteoporosis has recently become a concern in both the medical and lay communities. Osteoporosis may be defined as a decrease in bone mass with maintenance of normal bone composition. The increase in bone fragility results in an increased incidence of fractures. The disease most commonly affects postmenopausal women, particularly Caucasians. It is estimated that 1.2 million fractures per year can be attributed to osteoporosis. These fractures cost the health care system approximately $18.1 billion per year. Given the magnitude of the health and attendant financial problems, osteoporosis deserves the attention of clinicians and researchers. This article will deal with the pathophysiologic processes, techniques for bone mineral determination, therapeutic regimens and the advisability of mass screening. The relationship between bone mineral content and fracture risk has not been clearly defined. If every American woman between the ages of 40 and 54 years were given a single bone mineral screening examination, the cost would be approximately $187.5 million/year. At this price and in the absence of accepted treatment programs, it does not seem prudent for radiologists or other physicians to recommend expensive mass screening.

Aged↗