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Biomedical subjects

J Jepsen

Publications and source records attributed to J Jepsen.

12 recordsLinked to original sources
PubMed1999

Conserved residues and their role in the structure, function, and stability of acyl-coenzyme A binding protein.

In the family of acyl-coenzyme A binding proteins, a subset of 26 sequence sites are identical in all eukaryotes and conserved throughout evolution of the eukaryotic kingdoms. In the context of the bovine protein, the importance of these 26 sequence positions for structure, function, stability, and folding has been analyzed using single-site mutations. A total of 28 mutant proteins were analyzed which covered 17 conserved sequence positions and three nonconserved positions. As a first step, the influence of the mutations on the protein folding reaction has been probed, revealing a folding nucleus of eight hydrophobic residues formed between the N- and C-terminal helices [Kragelund, B. B., et al. (1999) Nat. Struct. Biol. (In press)]. To fully analyze the role of the conserved residues, the function and the stability have been measured for the same set of mutant proteins. Effects on function were measured by the extent of binding of the ligand dodecanoyl-CoA using isothermal titration calorimetry, and effects on protein stability were measured with chemical denaturation followed by intrinsic tryptophan and tyrosine fluorescence. The sequence sites that have been conserved for direct functional purposes have been identified. These are Phe5, Tyr28, Tyr31, Lys32, Lys54, and Tyr73. Binding site residues are mainly polar or charged residues, and together, four of these contribute approximately 8 kcal mol-1 of the total free energy of binding of 11 kcal mol-1. The sequence sites conserved for stability of the structure have likewise been identified and are Phe5, Ala9, Val12, Leu15, Leu25, Tyr28, Lys32, Gln33, Tyr73, Val77, and Leu80. Essentially, all of the conserved residues that maintain the stability are hydrophobic residues at the interface of the helices. Only one conserved polar residue, Gln33, is involved in stability. The results indicate that conservation of residues in homologous proteins may result from a summed optimization of an effective folding reaction, a stable native protein, and a fully active binding site. This is important in protein design strategies, where optimization of one of these parameters, typically function or stability, may influence any of the others markedly.

Acyl Coenzyme A↗
PubMed1998

Recent changes in Danish law on drugs and drug offences.

The article recounts changes in Danish Drug Law and Enforcement since the beginning of the 1990s and relates them to general trends in Danish criminal policy during the period. In addition to the implementation of EU directives, e.g. on money laundering and growth hormones, legislation has been passed to curb conspicuous dealing of drugs in the streets of Copenhagen. This part of the legislation is seen as a reaction to public fears and reactions to visible aliens dealing in drugs in a conspicuous way, albeit in minor quantities. The legal changes imply a considerable rise in penalties for repeated dealings in minor quantities and easier access to deportation of aliens. The latter has been criticized as potential violation of the human rights of aliens. This and other recent changes in criminal law and related legislation is seen as an indication of politicians' concerns with voters' anxieties, possibly at the edge of moral panics.

Criminal Law↗
PubMed1997

A two-site lectinoenzymatic assay for determination of tumour marker glycoproteins in rectal secretions.

A method is described for a titre-tray based two-site lectinoenzymatic assay of glycoproteins. WGA lectin, reacting with the core-part of glycans, was combined with lectins PNA and DBA, the latter two reacting with terminal parts of glycans. A standard curve was obtained with bovine submaxillary gland asialomucin, and measurements of human rectal secretion were calibrated against this curve. The assay showed an intra-assay reproducibility of 2.4-7.5%, and inter-assay reproducibility of 3.9-20.8%. Recovery tests showed a linearity close to predicted values. The selected standard was ideal as inhibition of lectin binding by monosaccharides showed similar inhibition profiles for human rectal secretion and for asialomucin standard. Neuraminidase treatment dramatically increased the PNA binding to human rectal secretion immobilized on WGA. Western blotting of human rectal secretion demonstrated a large range of lectin-reactive glycoproteins, the main fraction reacting with all lectins being approximately 250 kDa. The assay described is well suited for studies of the glycan part of tumour marker glycoproteins, and changes occurring in these. It has a high sensitivity by ignoring that the glycans may be present on different molecules. Examination of rectal secretions from various cancer patients showed significantly increased PNA binding, as well as an increased PNA/DBA binding ratio, in patients with colorectal cancer (p<3x10(-3)) and, unexpectedly, in patients with other cancers (p<5x10(-3)).

Animals↗
PubMed1986

Indicators of criminal involvement: crime rates versus qualitative classification of official records.

On the basis of a study of the registered criminality committed before and during treatment by 42 patients in long-term methadone treatment in Copenhagen, Denmark, it is argued that crime rates based on official records (such as the number of sanctioned offenses, or charges, or arrests, per year at risk) distort the picture of drug users' actual criminality unnecessarily. An alternative use of official records is suggested, and the results obtained accordingly are compared to those obtained by computing crime rates.

Adolescent↗
PubMed1985

Effect of postoperative extradural morphine on lower urinary tract function.

The effect of postoperative extradurally administered morphine on lower urinary tract function was studied in female patients undergoing uterine surgery. Urodynamic measurements were made on the day before and on the day after the operation, using a DISA 2-channel carbon dioxide (CO2) cystomictrograph. In ten patients without postoperative urinary retention no changes in cystometry were found during morphine administration, while two patients who developed acute urinary retention had a marked increase in bladder capacity and of detrusor pressure. In contrast, the urethral pressure profile was unchanged in both groups of patients. Intravenously administered naloxone tended to normalize the bladder capacity in the patients with urinary retention. These findings seem to indicate a marked effect in some patients of extradurally administered morphine and the acute urinary retention, following morphine administration, may be treated with naloxone.

Adult↗