Biomedical subjects

M Häggström

Publications and source records attributed to M Häggström.

4 recordsLinked to original sources

PubMed2002

Intestinal pHi studied with continuous saline tonometry during ischaemia and reperfusion in the pig.

OBJECTIVE: To evaluate continuous saline tonometry for detection of progressive intestinal ischaemia and reperfusion in a porcine model. DESIGN: In eight anaesthetised pigs, small bowel mucosal pCO2 was recorded by means of two identical equipments for continuous saline tonometry and a standard tonometry balloon during ischaemia and reperfusion. RESULTS: Both systems of saline tonometry functioned stably during the four hour protocol ischaemia, although not significant until after 45 min for one of the tonometers. CONCLUSION: The equipment for continuous saline tonometry has a good reactivity, an accuracy comparable with standard tonometry.

Animals↗

PubMed2001

Validation of a novel method for continuous saline tonometry in a porcine model.

Only intermittent and semi-continuous tonometric measurement of gastric and intestinal pHi is possible with the equipment available today. Earlier we developed a system for continuous saline tonometry and tested it in vitro. To assess the in vivo reliability of this method for continuous gastrointestinal saline tonometry, a standard tonometer for measurement of intestinal pCO2 and corresponding pHi was modified to allow continuous perfusion of physiological saline in a closed system and tested in a porcine model. In 11 anaesthetized and haemodynamically stable pigs, two continuous tonometry balloons were inserted into the distal small bowel, and a standard tonometry balloon was used as reference. To test long-term function of the continuous tonometers the research protocol lasted for eight hours. The two continuous saline tonometers performed well, and after an equilibration time of three hours the mean pHi values were stable between 7.35 and 7.43 and between 7.32 and 7.39 respectively. The standard tonometer measured stable pHi values. These preliminary studies indicate that continuous saline tonometry performs well over eight hours with a small bias and a good precision.

Animals↗

PubMed1986

GENEUS, a computer system for DNA and protein sequence analysis containing an information retrieval system for the EMBL data library.

We describe a comprehensive computer system, GENEUS, for extensive DNA, RNA and protein sequence analysis. The analysis system is developed for the DEC VAX/VMS computer and uses the EMBL Nucleic Acid Sequence Data Library. Help information is available on-line on terminal screen. To speed up system handling, a qualifier oriented user communication is employed. All results are stored on files making them accessible to the computer editor. An information retrieval system for the EMBL Nucleotide Sequence Data Library is also described. A defined data-base interface allows connection to other analysis programs.+

Amino Acid Sequence↗

PubMed1983

Search algorithm for pattern match analysis of nucleic acid sequences.

A new type of search algorithm to find biological information inherited in nucleic acid sequences was developed. The algorithm is of pattern match type and is based on the fact that genetic information often is a function of a predictable statistical occurrence of the four bases within parts of the sequence. The search algorithm compares the known statistical pattern of bases in e.g. a promoter, with an unknown sequence and calculates the statistical significance of the match at all positions in the unknown sequence. The program was tested on 54 published prokaryotic promoters. 44 or 49 could be found with 1 or 4 false answers, respectively. The program was also used on plasmid pBR322. All promoters functioning in an in vitro transcription system were found (tet, anti-tet, p4, bla and ori) except the so called p5 promoter. A search for donor and acceptor sites was performed in a human HLA genomic sequence that contains six introns. Five of the possible six donor and acceptor sites were found.

Base Sequence↗