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Biomedical subjects

G B Petersen

Publications and source records attributed to G B Petersen.

15 recordsLinked to original sources
PubMed1992

Ring chromosome 22 and neurofibromatosis.

Variable constitutional mosaicism, mos45,XY,-22/46,XY,-22,+mar/46,XY,-22,+r(22)/47,XY,-22,+r(22)+mar/ 47, XY,-22,+r(22)*2, was found in PHA-stimulated peripheral blood, in a lymphoblastoid cell line and in cultured skin fibroblasts from a mentally retarded patient with neurofibromatosis. Both the ring chromosome and the small extra marker chromosome stained positively by in situ hybridization with a chromosome 14/22-specific alphoid repeat probe. DNA dosage analysis showed constitutional loss of one copy of the arylsulfatase A gene (ARSA), consistent with its terminal location on 22q. There was no evidence of constitutional loss of D22S1 or D22S28 which flank the neurofibromatosis type 2 (NF2) locus. Analysis of two DNA samples from a skin neurofibroma indicated retainment of two copies of D22S1, whereas the results were ambiguous with respect to tumor-specific loss of one copy of D22S28. It is suggested that the development of neurofibromatosis of unclear type in two r(22) carriers might be associated with somatic mutation of the NF2 locus due to instability of the ring chromosome(s), and in analogy, that somatic mutation of either NF1 or NF2 may account for some cases of neurofibromatosis which do not meet the criteria of either NF1 or NF2. The occurrence of seminoma in the proband may be fortuitous, but could also be due to the presence of a seminoma-associated locus on chromosome 22.

Adult↗
PubMed1992

Ovine follistatin: characterization of cDNA and expression in sheep ovary during the luteal phase of the oestrous cycle.

We have isolated ovine follistatin cDNA from an ovarian follicle cDNA library and determined its sequence. The deduced amino acid sequence of the ovine follistatin precursor is highly homologous (greater than 97%) to the porcine, human and rat follistatins. Northern analysis was used to characterize follistatin gene expression in ovaries of adult ewes, collected from days 11 to 13 of the oestrous cycle. Two major (about 2.7 kb and 1.5 kb) and one minor (about 0.5 kb) transcripts were detected in polyadenylated RNA extracted from ovarian follicles and corpora lutea. The degree of expression of the transcripts varied in the two ovarian compartments, with the 2.7 kb species predominating in the follicles and the 1.5 kb species being more abundant in the corpora lutea. No transcripts were detected in stromal tissue containing preantral follicles of less than 1 mm.

Amino Acid Sequence↗
PubMed1979

Genetic studies of complement C4 in man.

A C4 variant found in about 5% of the population is described. The fast-moving part of this variant is governed by an allele (Fx) codominant to F. The Fx allele is in very strong linkage disequilibrium with HLA-B17 as the linkage disequilibrium parameter accounted for nearly 100% of the haplotype frequency of B17,Fx. The strong association is also evidenced by the study of 11 families segregating for the Fx allele. There was no instance of recombination between C4 and HLA in 36 informative meioses.

Adult↗
PubMed1979

Prenatal diagnosis of polycystic kidneys and encephalocele (Meckel syndrome).

Two unrelated families are presented with repeated occurrences of a congenital syndrome of which the main stigmata were polycystic kidneys and occipital encephalocele (Meckel syndrome). Prenatal diagnosis, followed by interruption of pregnancy, was performed in one case. The diagnosis was based on an increase of amniotic alpha-fetoprotein (AFP), and on the mode of growth and cell types of cultured amniotic cells. In another similarly examined case the diagnosis was suspected, but the parents did not wish the pregnancy to be interrupted. The child was stillborn and malformed. AFP values are presented and discussed in relation to the observed malformations. Neural tube defects are associated with an increase of AFP in amniotic fluid, but, as in normal pregnancies, the values decrease with increasing gestational age. On the other hand, kidney malformations seem to be associated with AFP values which remain high or even increase with increasing gestational age.

Amniotic Fluid↗
PubMed1978

The degradation of DNA by hydrazine: identification of 3-ureidopyrazole as a product of the hydrazinolysis of deoxycytidylic acid residues.

The reaction of hydrazine with the cytosine residues of DNA yields 3-ureidopyrazole, in approximately 50% yield, in addition to the expected 3-aminopyrazole. This product has been identified by ultraviolet, infrared, nuclear magnetic resonance and mass spectroscopy. A product of the reaction of hydrazine hydrate with cytosine, formulated by others as NN'-di-(3-pyrazolyl) hydrazine, has been identified as 3-ureidopyrazole.

Animals↗
PubMed1978

Association between coronary heart disease and the C3F-gene in essential hypertension.

The occurrence of the C3F allele was investigated in the following three groups: 69 consecutive referred patients with untreated essential hypertension, including borderline hypertension; 70 patients with established and treated essential hypertension, already attending the same outpatient clinic, and 62 age- and sex-matched normotensive healthy subjects without clinical signs of atherosclerosis or familial predisposition to hypertension. In the three groups the C3F allele was found in 38.2%, 29% and 20%, respectively. Among the treated hypertensive patients with C3F gene, 40% had coronary heart disease (CHD) compared to 6.1% among the C3F negative (P less than 0.005), and the relative risk of CHD among the treated hypertensive patients with this allele was found to be 10.2 (P less than 0.002). The C3F gene was present in 72.7% of the treated patients with CHD. In the untreated patients the occurrence of CHD was low, and no differences between C3F positive and negative patients could be demonstrated. No association of the C3F allele with familial predisposition to hypertension was found. This study provides further evidence of a positive association of the C3F allele with atherosclerosis, and it is concluded that this allele in a hypertensive patient might accelerate the atherosclerotic process, with subsequent premature development of vascular complications.

Adolescent↗
PubMed1977

Automated sequencing of insoluble peptides using detergent. Bacteriophage fl coat protein.

Peptides which are highly nonpolar and insoluble under moderate conditions of pH and ionic strength cannot be subjected to automated sequence analysis. We report a method for solubilization of one such peptide, bacteriophage fl coat protein, by chemical modification in the presence of sodium dodecyl sulfate. Following this treatment the 50-residue peptide was degraded stepwise in an automated sequenator using a single cleavage Quadrol program with high repetitive yield through residue 47. We also report a modified program using detergent incorporated into dimethylallylamine buffer which permitted sequencing with high repetitive yields for at least the first 18 residues of the unmodified and otherwise highly insoluble coat protein. The presence of detergent caused no observable difficulties in detection of residues by gas chromatography, thin layer chromatography, or amino acid analysis.

Amino Acid Sequence↗
PubMed1977

Congenital malformation of the feet with low body height. A new syndrome, caused by an autosomal dominant gene.

Among 75 members of a Danish family, 12 were found with a syndrome not previously described. Clinically, the syndrome consists of low body height and rigid flat feet, with weight-bearing pain in the feet. Radiologically, the deformation of the feet is a medial synostosis between the talus and the calcaneus combined with ankle joint dysplasia. The cause of the syndrome is most probably an autosomal dominant gene with complete penetrance. No linkage was found of the gene to 18 marker genes.

Adult↗
PubMed1975

Stability of pyrimidine oligodeoxyribonucleotides released during degradation of deoxyribonucleic acid with formic acid-diphenylamine reagent.

A small release of Pi from a diphenylamine-formic acid digest of DNA was detected after elimination of interpurine phosphodiester bonds was complete. Minor components in the DNA digest were identified as pyrimidine oligonucleotides which had lost one terminal phosphate. Isolated pyrimidine tracts released Pi on redigestion with the formic acid-diphenylamine reagent in amounts that increased with the number of nucleotides in the oligonucleotide taken. The oligonucleotides were also partially degraded by the formic acid-diphenylamine reagent and the degradation (2-3% of phosphodiester bonds between consecutive nucleotides) was almost independent of chain length. The cleavage was random with no preference for a phosphodiester bond flanked by particular nucleosides. This minor lack of specificity in the formic acid-diphenylamine-catalysed degradation of DNA can, however, account for the low recoveries of long pyrimidine tracts previously reported. Any analysis of pyrimidine tracts in a DNA molecule should make some correction for this small degree of degradation if exact assignments of the numbers of pyrimidine tracts are to be made.

Aniline Compounds↗
PubMed1975

Data on the HL-A linkage group.

Lod scores from a study in 229 families of the linkage relations of HL-A-PGM3 to 19 marker loci and cystic fibrosis are reported. The data exclude that ADA belongs to this linkage group while they give weak support for the inclusion of P. There is weak evidence for linkage of cystic fibrosis to PGM3, but none for linkage to HL-A. No new suggestive linkages appeared.

Blood Group Antigens↗
PubMed1975

Assessment of verapamil in the treatment of angina pectoris.

A brief review is given of the pharmacological data of verapamil, which chemically shows a certain similarity to papaverine. The effect of the drug (80 mg) 3 times daily, on angina pectoris, as compared with placebo, was evaluated in a double-blind cross-over therapeutic trial with 4-wk periods in 47 patients. The incidence of attacks and the nitroglycerine consumption decreased in the second fortnight of the verapamil period by approximately 25% compared with the placebo period. An ergometer test showed a prolongation of the exerice time of 20%. The mean blood pressure and the heart rate fell under verapamil treatment if the patients had values which were relatively high in the placebo period. The increase in heart rate during exercise from two different resting levels showed a tendency to become more pronounced under treatment with verapamil than under placebo. The length of the P-Q intervals were not affected by verapamil. The mechanism of action in angina pectoris is discussed, but it is concluded that it is still not possible to explain it. Twelve Danish medical departments took part in the trial.

Aged↗