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H B Rasmussen

Publications and source records attributed to H B Rasmussen.

At least 37 records · Page 2Linked to original sources
PubMed1998

Quantification of the N-terminal propeptide of human procollagen type I (PINP): comparison of ELISA and RIA with respect to different molecular forms.

This paper compares the results of procollagen type I N-terminal propeptide (PINP) quantification by radioimmunoassay (RIA) and enzyme linked immunosorbent assay (ELISA). PINP in serum from a patient with uremic hyperparathyroidism was measured in RIA and ELISA to 20 micrograms l-1 and 116 micrograms l-1 and the corresponding concentrations in dialysis fluid were 94.5 micrograms l-1 and 140 micrograms l-1, respectively. PINP antigen appears in two distinct peaks following size chromatography and the two peak fractions display immunological identity and identical M(r)'s (27 kDa: SDS-PAGE). Analysis of fractions from size separated amniotic fluid, serum and dialysis fluid demonstrated that the RIA failed to measure the low molecular weight form of PINP. However, the anti-PINP supplied with the RIA-kit and the anti-PINP applied in the ELISA reacted equally well with both molecular forms of PINP when analysed in a direct ELISA. It is concluded that the major difference in the ELISA and RIA results is due to assay efficacy with respect to the low molecular weight form of PINP.

Amniotic Fluid↗
PubMed1998

Large number of polymorphic nucleotides and a termination codon in the env gene of the endogenous human retrovirus ERV3.

The terminal portion of the pol gene and the entire env gene of the human endogenous retrovirus ERV3 was screened for polymorphic nucleotides. For this purpose fragments amplified from the desired regions of ERV3 were subjected to single strand conformational analysis (SSCP analysis). Using this approach, we detected 13 polymorphic nucleotides, namely four in the pol gene and nine in the env gene. Three of the nucleotide substitutions were synonymous (not affecting the amino acid code). One of the non-synonymous nucleotide substitutions changed an arginine codon to a termination codon. The alleles at the different polymorphic sites could be arranged into five ERV3 haplotypes, two of which were new. To evaluate the possible significance of the termination codon, which precludes expression of a putative immunoregulatory factor, we examined samples of DNA from patients with multiple sclerosis, a demyelinating disease of presumed autoimmune etiology. We did not find an association between the ERV3 allele with the termination codon and this disease. Perhaps the presence of a stop codon combined with the high number of non-synonymous nucleotide substitutions in the reading frame of the env gene reflects absence of selective constraints during evolution. Obviously, our findings contradict the assumption that the reading frame of the ERV3 env gene has been conserved throughout evolution.

Codon, Terminator↗
PubMed1997

Possible involvement of endogenous retroviruses in the development of autoimmune disorders, especially multiple sclerosis.

Endogenous retroviruses are normal elements in vertebrate genomes. Many aspects concerning these genomic elements are still uncertain. In mice some endogenous retroviral sequences seem to be involved in the regulation of immune responses and there is even evidence that a retroviral element is responsible for the development of an autoimmune disease in a mouse strain. Whether endogenous retroviruses also contribute to the development of autoimmune diseases in humans is not known, but it is an interesting possibility. Below we briefly review endogenous retroviruses as potential etiological factors in autoimmunity and we discuss a possible association between MS and endogenous retroviruses on the basis of results from our laboratory.

Animals↗
PubMed1997

Expression of endogenous retroviruses in blood mononuclear cells and brain tissue from multiple sclerosis patients.

OBJECTIVES: To compare the expression of endogenous retroviruses in MS patients and controls. MATERIAL AND METHODS: Peripheral blood mononuclear cells were obtained from 22 MS patients, a corresponding number of matched healthy donors and five patients with other central nervous system disease. Also brain specimens from MS patients and controls were obtained. Transcripts of various endogenous retroviruses in these samples were detected by RNA-PCR. RESULTS: Several endogenous retroviral sequences were transcribed in peripheral blood mononuclear cells and brain tissue from MS patients as well as controls. A composite transcript of an endogenous retrovirus and a zinc finger sequence was more frequently found in healthy donors than in MS patients. CONCLUSION: Some endogenous retroviruses are normally transcribed in white blood cells and brain tissue. The significance of those findings, which concerned the composite transcripts of the zinc finger sequence and its associated endogenous retrovirus is uncertain.

Adult↗
PubMed1997

Serum concentration of the aminopropeptide of type I procollagen in patients on haemo- and peritoneal dialysis.

Using an ELISA technique, the aminopropeptide of type I procollagen (PINP) was measured in serum from patients with chronic renal failure treated with haemodialysis (HD) (n = 19) or continuous ambulatory peritoneal dialysis (CAPD) (n = 14), and compared to the commonly used bone markers. The serum concentrations for PINP, compared to healthy controls were significantly increased in both the HD-group (p < 0.00001) and the CAPD-group (p < 0.00001). In the HD-group a close correlation was found between PINP and parathyroid hormone (PTH) (R(s) = 0.745; p = 0.00026) and between PINP and total alkaline phosphatase (R(s) = 0.623; p = 0.004), but in the CAPD-group the corresponding p-values were 0.17 and 0.06 only. No significant difference was found between the HD and CAPD patients with respect to serum levels of PINP, PTH, total alkaline phosphatase, or ionized calcium. In the HD-patients, a significantly higher level of serum phosphate was found compared to in the CAPD-patients. The present study demonstrates a close correlation between PTH, total alkaline phosphatase and PINP, which indicates that PINP might be used as a marker for evaluating increased bone turnover in patients with chronic renal failure treated with haemodialysis, and perhaps also in patients treated with peritoneal dialysis, and that the ideal biochemical parameters to analyse changes in bone metabolism in these patients may be a combination of the initiating hormone (PTH) and PINP as a marker of the effect of PTH on bone metabolism.

Adolescent↗
PubMed1996

Biosynthesis of cyanohydrin glucosides from unnatural nitriles in intact tissue of Passiflora morifolia and Turnera angustifolia.

Passiflora morifolia, which under natural conditions contains cyanohydrin glucosides linamarin, lotaustralin and epilotaustralin, converted cyclopentanecarbonitrile, 2-cyclopentenecarbonitrile and 3-methylbutanenitrile into the corresponding cyanohydrin glucosides. Turnera angustifolia, which normally produces glucosides of cyclopentenone cyanohydrin, converted cyclopentanecarbonitrile, 2-methylpropanenitrile and 2-methylbutanenitrile, but not 3-methylbutanenitrile, into the corresponding cyanohydrin glucosides. Mixtures of epimers were produced when these glucosides contained chiral cyanohydrin carbon atoms. Feeding with cyclopentanecarbonitrile resulted in formation of 1-(beta-D-glucopyranosyloxy)cyclopentanecarbonitrile, a saturated analogue of deidaclin and tetraphyllin A. Neither plant utilized cyclopropanecarbonitrile as substrate. The experiments demonstrate broad substrate specificity of nitrile hydroxylases present in these plants. A novel glycoside, 2-[6-O-(beta-D-xylopyranosyl)-beta-D-glucopyranosyloxy]propane (isopropyl primeveroside), was isolated from P. morifolia. The compound represents a rare example of natural isopropyl glycoside; its characterization included assignment of all 1H and 13C NMR signals of the primeverosyl group using two-dimensional NMR methods. Biosynthesis of the isopropyl moiety of the primeveroside is unclear, but the formation of alcohols corresponding to natural cyanohydrins may be a previously unrecognized extension of the cyanohydrin biosynthesis pathway in higher plants.

Biotransformation↗
PubMed1996

Sequencing and detection of polymorphisms in the 5' end of the human endogenous retroviral element, HRES-1.

Fragments of the 5' long terminal repeat (LTR) of the human endogenous retroviral element, HRES-1, were amplified. Single strand conformation analysis of these fragments in combination with sequencing revealed two polymorphic nucleotides, namely a HindIII and an Eco571 polymorphic site. Moreover, a number of differences from the previously published HRES-1 LTR sequence were detected. The linkage pattern of the two polymorphisms suggested the existence of three allelic forms of HRES-1. The frequencies of the genotypes and alleles of HRES-1 were determined in 158 individuals. The detection of HRES-1 markers may be useful to study associations between this endogenous retrovirus and various diseases.

Base Sequence↗
PubMed1996

Possible association between multiple sclerosis and the human T cell leukemia virus (HTLV)-related endogenous element, HRES-1.

In the present study we searched for an association between the human endogenous retroviral element HRES-1 and multiple sclerosis (MS). Fragments of this endogenous retrovirus were amplified for subsequent examination by single strand conformational analysis. We did not find HRES-1 markers exclusively linked with MS and only the two already known polymorphisms, which define three alleles of HRES-1, were detected. However, we found a significant difference in the distribution of these alleles between a group of 87 MS patients and a control group of 158 healthy individuals (P = 0.014). There were no differences in the distribution of the HRES-1 allelic forms between MS patients with a relapsing-remitting course and patients with chronic progressive MS. Our results provide evidence of an association between HRES-1 and MS. Possible explanations for this are discussed.

Alleles↗
PubMed1996

Three allelic forms of the human endogenous retrovirus, ERV3, and their frequencies in multiple sclerosis patients and healthy individuals.

A possible association between the endogenous retrovirus, ERV3, and multiple sclerosis (MS) was examined. Samples of DNA from 74 MS patients and 159 healthy blood donors were subjected to enzymatic amplification followed by single strand conformational analysis to detect polymorphisms in the long terminal repeats of ERV3. Using this approach we detected six single base pair variations and a drop-out of a nucleotide. The linkage pattern of these base pair variations enabled us to define three allelic forms of ERV3. Polymorphisms exclusively present in the group of patients were not found and the distribution of the three allelic forms did not differ significantly between the group of controls and the MS group. Neither was there a significant difference in the distribution of the three alleles between MS patients with the progressive form and patients with relapsing/remitting MS. Our results are not in support of an association between ERV3 and MS.

Alleles↗
PubMed1995

Anaerobic biodegradation potentials in digested sludge, a freshwater swamp and a marine sediment.

An anaerobic gas production test was used for determining the potential biodegradation of 22 organic chemicals under methanogenic conditions. Nine of the examined chemicals were extensively mineralized (> 75%) both in sewage sludge and in a freshwater swamp indicating good agreement between biodegradation potentials in these habitats. Samples from a marine sediment showed a less extensive mineralization of most of the test chemicals, and lag periods of several weeks often preceded net gas production. As marine sediments usually contain sulfate at the time of collection, the assessment of biodegradation potentials in such environments is probably more reliable when using a method based on sulfate reduction instead of methanogenic gas production. The results of the tests indicate that the commonly recommended washing of sludge solids can be eliminated by applying a more diluted inoculum.

Anaerobiosis↗
PubMed1995

Expression of endogenous retroviruses in blood mononuclear cells and brain tissue from multiple sclerosis patients.

The aim of the present study was to examine whether there is an abnormal expression of certain endogenous retroviruses in MS patients. For this purpose samples of peripheral blood mononuclear cells were obtained from 22 MS patients, a corresponding number of age and sex-matched healthy donors and five patients with other diseases affecting the central nervous system. In addition, brain specimens of macroscopic normal white and gray matter from four MS patients and a similar number of controls were included in the study. Using an enzymatic amplification technique, we found expression of the endogenous retroviral sequences, HRES-1, HERV-K10 and ERV3 in most samples of peripheral blood mononuclear cells from MS patients and controls without obvious differences between these two groups. In contrast, composite transcripts of ERV3 and a zinc finger sequence were more frequently detected in healthy donors than in MS patients. At present, the possible significance of this is uncertain. The retroviral element 4-1 was not transcribed or only transcribed at a very low level in peripheral blood cells of controls and MS patients. Transcripts of various endogenous retroviruses were also detected in the brain samples, but a different pattern was not apparent in the MS group as compared with controls. Aspects concerning a possible association between endogenous retroviruses and autoimmunity are considered.

Adult↗
PubMed1994

Combined polymerase chain reaction-hybridization microplate assay used to detect bovine leukemia virus and Salmonella.

Here we describe the use of an assay that integrates the polymerase chain reaction (PCR) with hybridization of the amplified product for detection in the same microwell. Traditional PCR requires transportation of the amplified product to another system for characterization of samples. Transportation means time-consuming manipulation and risk of contaminating the laboratory with amplified product. Integration of amplification and specific product detection greatly reduces sample manipulations and the risk of contamination. We used the assay for detection of bovine leukemia virus and Salmonella. The results were identical with those produced by two traditional PCR methods. This assay could easily be adapted for other organisms, simply by using other primers and probes.

Base Sequence↗
PubMed1993

Fetal antigen 1 (FA1) in the human pancreas: cell type expression, topological and quantitative variations during development.

Monospecific rabbit anti-human fetal antigen 1 (FA1), was used to examine the distribution of FA1 during the development of the human fetal pancreas and liver using an indirect immunoperoxidase technique. FA1 was expressed by 94% of the glandular epithelial cells of the branching ducts in the pancreatic anlage at week 7 of gestation. This pattern changed during the development of the human pancreas, 64% of the glandular cells being FA1 positive at week 17 of gestation, decreasing to 11% in the infant (4 months after birth). In the infant and adults the FA1 expression was restricted to a subpopulation of beta-cells within the islets of Langerhans. Insulin immunoreactive cells were scattered throughout the epithelium of primitive branching pancreatic ducts at week 7 of gestation, well before the formation of islets. From the 7th through to the 17th week of gestation, FA1 was found in the cytoplasm of fetal hepatocytes, whereas no staining was observed in the liver from a 4-month-old infant. No FA1 expression was found in the epithelium of the developing gut. The present findings indicate that the glandular epithelial cells in the developing pancreas may serve as stem cells, which, if appropriately induced, may differentiate into endocrine cells. Fetal antigen 1 (FA1) may take part in or be a result of this differentiation.

Adult↗
PubMed1993

Studies on the isolation, structural analysis and tissue localization of fetal antigen 1 and its relation to a human adrenal-specific cDNA, pG2.

Fetal antigen 1 was purified from second trimester human amniotic fluid by immunospecific affinity chromatography followed by reversed-phase chromatography. Fetal antigen 1 is a single chain glycoprotein with a M(r) of 32-38 kDa. The amino acid composition revealed a high content of cysteines, prolines and amino acids (aa) with acidic side-chains indicating that fetal antigen 1 is a compactly folded, strongly hydrophilic molecule. The N-terminal amino acid sequence (37 aa) revealed no homology to other known protein sequences, implying that fetal antigen 1 is a 'novel' human protein. When the aa sequence was back-translated into the appropriate degenerate sequence of nucleic acids, fetal antigen 1 could be partially aligned to a 'human adrenal-specific mRNA, pG2'. The indirect immunoperoxidase technique demonstrated fetal antigen 1 in fetal hepatocytes, glandular cells of fetal pancreas and in fetal adrenal cortex, whereas fetal medullary cells were fetal antigen 1 negative. In adult specimens fetal antigen 1 was exclusively found within the beta cells of the islets of Langerhans and in the adrenals with pronounced staining in the cortex. Our observations suggest that fetal antigen 1 is encoded by the mRNA defined by the cDNA clone pG2, but definitive sequencing and expression studies of this mRNA have not been achieved.

Adrenal Glands↗
PubMed1993

Do endogenous retroviruses have etiological implications in inflammatory and degenerative nervous system diseases?

Vertebrates carry large numbers of endogenous retroviruses (ERVs) and related sequences in their genomes. These retroviral elements are inherited as Mendelian traits. Generally, ERVs are defective without the ability of being expressed as viral particles. However, ERV sequences often have a potential for expression of at least some proteins. So far, the possible biological significance of ERVs is not clear. Nonetheless, there are observations suggesting a connection between ERVs and various diseases. This is the case with murine lupus and a spinal cord disease of certain mouse strains. In the present review, we discuss possible mechanisms by which ERVs could contribute to the development of human degenerative and inflammatory nervous system diseases, including direct effects on nervous system cells and immune cells. Interactions between ERVs and infectious viruses are also discussed. Finally, we review a possible retroviral etiology of multiple sclerosis.

Animals↗