Biomedical subjects

B Sartorius

Publications and source records attributed to B Sartorius.

4 recordsLinked to original sources

PubMed2006

Description of a new all cause mortality surveillance system in Sweden as a warning system using threshold detection algorithms.

A warning system has been set up to detect unusual weekly clusters of deaths by age group and municipality using all-cause Swedish death registry data. The technique for monitoring deaths by age group (<1, 1-24, 25-44, 45-64 and 65 plus) and week uses a compound smoothing technique, which calculates a baseline of expected events from retrospective data. Due to insufficient baseline data for the geographical component of the system a different algorithm, based on the Poisson distribution, was chosen to calculate expected weekly number of deaths per municipality, adjusting for municipalities with inherently higher mortality rates. This system was designed and tested during 2004 and implemented from the beginning of 2005. Threshold settings have been adjusted to provide a realistic number of weekly alerts. An evaluation of the system will be performed prospectively from the beginning of 2005 due to the lack of a gold standard for retrospective performance evaluation.

Adolescent↗

PubMed2005

An outbreak of mumps in Sweden, February-April 2004.

Between 24 February and 26 April 2004, Västra Götaland county in Sweden reported 42 cases of suspected mumps. A descriptive study of the cases was undertaken. A questionnaire was administered by telephone and vaccine effectiveness was calculated using the screening method. Seventy four per cent (31/42) of the suspected cases were interviewed by telephone. Eight out of the 42 serum samples were positive or equivocal for mumps IgM by ELISA. Mumps virus genome was identified in 21/42 (50%) saliva samples. Eleven were selected for sequencing and all were confirmed to be mumps virus. Cases were predominantly from 2 small towns. Eighteen out of 19 cases that developed bilateral swelling could be linked to one small town. The median age of interviewed cases was 43 years (range 5 to 88). Six cases were admitted to hospital, 5 of which were older than 30 years. The highest incidence occurred in the 35 to 44 years age group. Vaccine effectiveness was estimated to be 65% for 1 dose and 91% for 2 doses. This descriptive study shows the increasing age of mumps cases with increasing vaccine coverage. Vaccine effectiveness was particularly high for 2 doses. Second-dose uptake must be ensured, as primary vaccine failure is well documented in mumps. Stronger precautions must be taken to avoid pools of susceptible older individuals accumulating due to the increased risk of complications.

Adolescent↗

PubMed2004

Nonlinear dynamics of semiconductor lasers with active optical feedback.

An in-depth theoretical as well as experimental analysis of the nonlinear dynamics in semiconductor lasers with active optical feedback is presented. Use of a monolithically integrated multisection device of submillimeter total length provides access to the short-cavity regime. By introducing an amplifier section as a special feature, phase and strength of the feedback can be separately tuned. In this way, the number of modes involved in the laser action can be adjusted. We predict and observe specific dynamical scenarios. Bifurcations mediate various transitions in the device output, from single-mode steadystate to self-pulsation and between different kinds of self-pulsations, reaching eventually chaotic behavior in the multimode limit.

Journal Article↗

PubMed1977

A cell membrane alteration specifically induced by SV40 transformation.

Transformation of mouse 3T3 cells by SV40 results in a specific membrane modification which renders cells resistant to the killing action of the lipophilic antibiotic Amphotericin B. This alteration is under genetic cellular control and is specific for SV40 transformation since transformation with polyoma or mouse sarcoma viruses does not confer resistance to the antibiotic. Analogous resistance is induced by SV40 transformation of primary human fibroblast cells. The acquired resistance is not due to decreased binding of Amphotericin B and is partially reversed if cells are grown in the presence of cholesterol. The results are interpreted as a specific change of sterol structure of the membrane or the loss of a minor cholesterol fraction responsible for the killing action of the antibiotic.

Amphotericin B↗