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Biomedical subjects

B Olsen

Publications and source records attributed to B Olsen.

At least 73 records · Page 4Linked to original sources
PubMed1995

Bacterial colonization of the larynx and trachea in healthy children.

Fifty healthy children were included in the study; tracheal and laryngeal aspirations were performed after oral endotracheal intubation during minor surgery. The aspirates were evaluated and examined in the same way as aspirates from children suspected of pneumonia; 31 samples were accepted for the final analysis. After culturing, specimens from 30 children exhibited growth of potential pathogenic bacteria either from the larynx, the trachea or both. Prior to culture, bacteria were seen by microscopy in 24 samples from 30 children. These results indicate that the majority of healthy children carry potential pathogenic bacteria, not only in the larynx but also to a certain extent in the trachea. We conclude that aspirates from the larynx and the trachea are of limited value in the diagnosis of bacterial pneumonia in children.

Adolescent↗
PubMed1995

Transhemispheric exchange of Lyme disease spirochetes by seabirds.

Lyme disease is a zoonosis transmitted by ticks and caused by the spirochete Borrelia burgdorferi sensu lato. Epidemiological and ecological investigations to date have focused on the terrestrial forms of Lyme disease. Here we show a significant role for seabirds in a global transmission cycle by demonstrating the presence of Lyme disease Borrelia spirochetes in Ixodes uriae ticks from several seabird colonies in both the Southern and Northern Hemispheres. Borrelia DNA was isolated from I. uriae ticks and from cultured spirochetes. Sequence analysis of a conserved region of the flagellin (fla) gene revealed that the DNA obtained was from B. garinii regardless of the geographical origin of the sample. Identical fla gene fragments in ticks obtained from different hemispheres indicate a transhemispheric exchange of Lyme disease spirochetes. A marine ecological niche and a marine epidemiological route for Lyme disease borreliae are proposed.

Animals↗
PubMed1994

[Urinary bladder diverticula].

We describe two patients with urinary tract infection and obstructive voiding problems which lasted for respectively 21 months and five years before a bladder diverticulum was diagnosed by cystography and cystoscopy. Both patients were operated on by open diverticulectomy. The post-operative courses were uneventful and both patients were relieved of urinary symptoms after surgery. The article includes a review of the literature on bladder diverticula.

Adult↗
PubMed1994

Steroid hormone regulation and tissue-specific expression of the human GnRH gene in cell culture and transgenic animals.

In order to study the molecular mechanisms involved in the control of GnRH gene expression, the human GnRH gene was cloned and characterized. The gene was expressed in cells obtained from CNS tumors in transgenic mice generated utilizing 1131 bp of 5' flanking GnRH DNA fused to the simian virus 40 large T antigen. We have shown a stimulatory estrogen response element in the human GnRH gene by transient transfection studies. DNase I footprinting and an avidinbiotin DNA binding assay demonstrated that the human GnRH gene bound ER. The GN cell line was found to have nuclear ERs utilizing an 125I estradiol binding study and by in situ hybridization histochemistry. In order to study GnRH expression in vivo, either 5000 or 484 bp of GnRH flanking DNA was fused to the luciferase (Luc) reporter gene, and transgenic mice generated. Expression in the transgenic animals was found in the hypothalamus of animals bearing the -5000Luc transgene, but not in animals bearing the -484Luc transgene. The transgenic mice expressing the -5000Luc gene were gonadectomized resulting in a 20-30% increase in hypothalamic Luc expression in the males and a 65% increase in females, while mice who were gonadectomized and replaced with testosterone (males) or E2 (females) showed a 50% decrease in Luc expression over control levels. Thus, these studies present in vitro evidence of E2 modulation of GnRH gene expression and an in vivo model in which sensitive studies of GnRH regulation and expression can be performed.

Animals↗
PubMed1994

Geographical distribution, host associations, and vector roles of ticks (Acari: Ixodidae, Argasidae) in Sweden.

This review covers the geographic distribution and host relationships of the tick species in Sweden. Ixodes uriae White, I. caledonicus Nuttall, I. unicavatus Neumann, I. arboricola Schulze & Schlottke, and I. lividus Koch are ornithophagous species. I. trianguliceps Birula, I. canisuga Johnston, I. hexagonus Leach, and Argas vespertilionis (Latreille) are mammalophagous. I. ricinus (L.) and Haemaphysalis punctata Canestrini & Fanzago feed on both birds and mammals. All these tick species may be considered to be permanently present in Sweden. I. persulcatus Schulze, Hyalomma marginatum Koch, and the brown dog tick, Rhipicephalus sanguineus (Latreille), may be regarded as not indigenous to Sweden although they may be regularly introduced by spring-migrating birds or imported dogs, respectively. The first European record of the American dog tick, Dermacentor variabilis (Say), is reported. There are several records of Hyalomma aegyptium (L.) from imported tortoises in Sweden. Excluding other ticks imported on exotic pets and zoo animals, another 13 tick species are listed that may occur, at least occasionally, in Sweden. Because of its wide geographic distribution, great abundance, and wide host range, I. ricinus is medically the most important arthropod in northern Europe. I. ricinus is common in southern and south-central Sweden and along the coast of northern Sweden and has been recorded from 29 mammal species, 56 bird species, and two species of lizards in Sweden alone. The potential introduction to Sweden of exotic pathogens with infected ticks (e.g., I. persulcatus and H. marginatum on birds or Dermacentor spp. and R. sanguineus on mammals) is evident.

Animals↗
PubMed1993

[Cystitis cystica--a premalignant condition?].

Although cystitis cystica is considered to be a premalignant disease of the urinary bladder, remarkably few reports document the progression from cystitis cystica and glandularis to carcinoma of the bladder. We describe three patients where cystitis cystica was demonstrated 12, three and one month before diagnosis of cancer. We believe cystitis cystica reflects mobilization of the humoral immune defence mechanism in response to various agents, among these a subclinical malignant tumour.

Aged↗
PubMed1993

[The health survey in Finnmark--satisfaction with hospital services].

Global satisfaction with hospital services was examined in a comprehensive population study (age group 20-62) in the county of Finnmark, Norway. Indicators of availability of and access to the health care services in general appeared to have considerable impact on the evaluation of hospital services. People were least satisfied in municipalities with a high rate of turn-over of general practitioners, and among respondents who had difficulty in getting in touch with a general practitioner. Further, geographical proximity to hospitals and shutting down of local hospitals significantly influenced satisfaction. Various measures of health status, chronic disease and use of health care services were found to have marginal or no impact. On the other hand, low satisfaction with life in general, length of education and high preoccupation with health appeared to increase dissatisfaction.

Adult↗
PubMed1992

An occipito-temporal syndrome in adolescents with optimally controlled hyperphenylalaninaemia.

The study included 16 adolescents with optimally controlled hyperphenylalaninaemia (McKusick 26160), of whom six did not require treatment according to conventional criteria. All except the two patients with lowest median serum phenylalanine level throughout childhood (most values at 200-300 mumol/L) had white matter abnormalities detectable with magnetic resonance imaging. The lesions were particularly prominent in the watershed regions between the posterior and middle cerebral arteries. In most patients with moderate or severe hyperphenylalaninaemia frontal white matter lesions were present as well. Normal proton magnetic resonance spectra indicated that the lesions were stable. Occipital EEG abnormalities were frequent, and deficient performance on a pattern-recognition test was a characteristic neuropsychological finding. Serum phenylalanine levels at about 300 mumol/L or below throughout childhood and early adolescence may be required to avoid lesions. The present study demonstrates the limitations of even an optimally controlled dietary regimen in hyperphenylalaninaemia.

Adolescent↗
PubMed1992

Comparative study of microsatellite and cytogenetic markers for detecting the origin of the nondisjoined chromosome 21 in Down syndrome.

Nondisjunction in trisomy 21 has traditionally been studied by cytogenetic heteromorphisms. Those studies assumed no crossing-over on the short arm of chromosome 21. Recently, increased accuracy of detection of the origin of nondisjunction has been demonstrated by DNA polymorphism analysis. We describe a comparative study of cytogenetic heteromorphisms and seven PCR-based DNA polymorphisms for detecting the origin of the additional chromosome 21 in 68 cases of Down syndrome. The polymorphisms studied were the highly informative microsatellites at loci D21S215, D21S120, D21S192, IFNAR, D21S156, HMG14, and D21S171. The meiotic stage of nondisjunction was assigned on the basis of the pericentromeric markers D21S215, D21S120, and D21S192. Only unequivocal cytogenetic results were compared with the results of the DNA analysis. The parental and meiotic division origin could be determined in 51% of the cases by using the cytogenetic markers and in 88% of the cases by using the DNA markers. Although there were no discrepancies between the two scoring systems regarding parental origin, there were eight discrepancies regarding meiotic stage of nondisjunction. Our results raise the possibility of recombination between the two marker systems, particularly on the short arm.

Base Sequence↗
PubMed1992

Ilizarov technique. Results and difficulties.

Of 100 cases treated by the Ilizarov method, 91 patients were reviewed from February 1985 to March 1990. There were 32 tibial fractures (29 open) and 21 nonunions (nine infected). There were 47 cases of limb lengthening (28 tibia and 19 femur). The results were as follows: good, 83%; fair, 13%; and poor, 4%. Slight and intermittent pain in some wire of the device was frequent (69%). Average bone healing time in tibial fractures was 4.95 months and 5.83 months in tibial nonunions. In bone-lengthening operations, the average lengthening index in the tibia was 1.02 months/cm (lengthenings ranged from 3 cm to 10 cm, with a mean of 5.71 cm), whereas in the femur, the average lengthening index was 1.14 months/cm (lengthenings ranged from 3 cm to 7 cm, with a mean of 5.34 cm). Manually-tensed wires produced frequent problems (24.5%), whereas wire tensed by the dynamometric tensioner produced problems in only 7.8% of the cases. Despite good results, the Ilizarov technique requires adequate training to reduce an overall complication rate (approximately 30%).

Adolescent↗