Search PubMed⌕ Search

Biomedical subjects

M Johansson

Publications and source records attributed to M Johansson.

At least 253 records · Page 14Linked to original sources
PubMed1992

Molecular cloning of a gene encoding porcine interferon-beta.

A gene encoding the porcine interferon-beta (poIFN-beta) was cloned from a genomic library. The sequence of a potential intronless coding region as well as 1,265 bp of the 5'- and 277 bp of the 3'-flanking regions is presented. The gene is predicted to encode a mature protein of 165 amino acids and a signal peptide of 21 amino acids. This probable poIFN-beta shows high homology (63%) with human (hu) IFN-beta at the amino acid level, but less with porcine (po) IFN-alpha 1 (32%). It contains three cysteines and three potential N-glycosylation sites. A region of the 5' flank (-116 to -159) of the gene is homologous to the IFN gene regulatory element (IRE) of the huIFN-beta gene which mediates virus inducibility. Southern blot analysis indicates that the poIFN-beta gene is present as a single copy in the porcine genome. Its expression in porcine peripheral blood leukocytes stimulated in vitro by pseudorabies virus (PRV) was demonstrated at the RNA level both by Northern blot analysis and by in situ hybridization. The latter approach in addition detected only about one IFN-beta mRNA-containing cell per 2,000 PRV-stimulated porcine leukocytes, a frequency in the same range as that for leukocytes containing IFN-alpha mRNA.

Amino Acid Sequence↗
PubMed1992

Cloning of highly polymorphic microsatellites in the horse.

We have isolated equine microsatellites by screening a genomic library with (TG)n and (TC)n probes. TG microsatellites were found to be more abundant than TC repeats, with an estimated frequency of one per 100,000bp. Sequence analysis of eight TG-positive clones revealed varying structures of the repeat regions; perfect stretches of TG repeats, imperfect stretches of TG repeats and compound regions of TG and TC repeats. Five loci were analysed by PCR and showed extensive polymorphism; three to seven alleles and heterozygosities of 0.40-0.76 were observed when screening 20-30 unrelated individuals. The high degree of polymorphism, their abundance and the possibility of automating the typing procedure make these loci ideal for standardized paternity testing in the horse. Furthermore, we demonstrate that single hairs can be used as starting material for the PCR analysis.

Animals↗
PubMed1992

Multiple restriction fragment length polymorphisms in the porcine calcium release channel gene (CRC): assignment to the halothane (HAL) linkage group.

Two cDNA probes for the porcine calcium release channel gene (CRC) were used in restriction fragment length polymorphism (RFLP) analysis in an attempt to develop genetic markers linked to the malignant hyperthermia (stress susceptibility) gene (HAL). Three TaqI RFLPs, denoted CRC1-CRC3, each composed of two alleles, were detected. RFLPs were also detected with MspI and PvuII, but the MspI RFLP correlated completely with CRC3 in this material and the PvuII RFLP could not be scored reliably due to a minute size difference between the two allelic fragments. The autosomal codominant inheritance of these RFLP loci was confirmed by family analyses. Significant evidence for genetic linkage between the CRC1/CRC3 loci and the A1BG locus in the HAL linkage group confirmed a previous assignment of the CRC gene to chromosome 6 in the pig.

Animals↗
PubMed1992

Effect of 4 days of mouth rinsing with delmopinol or chlorhexidine on the vitality of plaque bacteria.

Delmopinol is a new surface active anti-plaque agent that has demonstrated a low antimicrobial effect in vitro. By use of a vitality staining technique, the antimicrobial effect on bacteria in plaque samples was tested after rinsing with delmopinol or chlorhexidine. 6 healthy male subjects volunteered to rinse for 4 days using a double-blind cross-over study design with a wash-out period between the rinsing regimens. No oral hygiene measures were allowed during the test periods and each test period started with a professional tooth cleaning procedure 2 days before the start of rinsing to allow for plaque formation. Rinsing was performed with 0.2% delmopinol hydrochloride or 0.2% chlorhexidine digluconate 2 x a day. Small samples of plaque were collected from the buccal surfaces of premolars and 1st molars before the first rinse on day 1 and then before and 1, 2, 4, 7, and 24 h after the last rinse on the 4th day. The plaque samples were immediately stained with propidium iodide and fluorescein diacetate to visualize dead and vital microorganisms respectively. The vitality of the microflora was evaluated using a fluorescence microscope. The baseline vitality values were 91% for chlorhexidine and 86% for delmopinol. At day 4, the plaque vitality for chlorhexidine was approximately 40% up to 4 h and 50% at 7 h and 60% at 24 h after the last rinse. Corresponding values for plaque vitality after delmopinol rinsing were between 70 and 80% on all sampling occasions.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteria↗
PubMed1992

Adaptation of mitochondrial ATP production in human skeletal muscle to endurance training and detraining.

The adaptation of mitochondrial ATP production rate (MAPR) to training and detraining was evaluated in nine healthy men. Muscle samples (approximately 60 mg) were obtained before and after 6 wk of endurance training and after 3 wk of detraining. MAPR was measured in isolated mitochondria by a bioluminometric method. In addition, the activities of mitochondrial and glycolytic enzymes were determined in skeletal muscle. In response to training, MAPR increased by 70%, with a substrate combination of pyruvate + palmitoyl-L-carnitine + alpha-ketoglutarate + malate, by 50% with only pyruvate + malate, and by 92% with palmitoyl-L-carnitine + malate. With detraining MAPR decreased by 12-28% from the posttraining rate (although not significantly for all substrates). No differences were found when MAPR was related to the protein content in the mitochondrial fraction. The largest increase in mitochondrial enzyme activities induced by training was observed for cytochrome-c oxidase (78%), whereas succinate cytochrome c reductase showed only an 18% increase. The activity of citrate synthase increased by 40% and of glutamate dehydrogenase by 45%. Corresponding changes in maximal O2 uptake were a 9.6% increase by training and a 6.0% reversion after detraining. In conclusion, both MAPR and mitochondrial enzyme activities are shown to increase with endurance training and to decrease with detraining.

Adenosine Triphosphate↗
PubMed1992

DNA fingerprinting in horses using a simple (TG)n probe and its application to population comparisons.

A synthetic polynucleotide (TG)n was hybridized to equine DNA digested with HinfI and hypervariable hybridization patterns were obtained. Mendelian inheritance of these DNA fingerprinting patterns was confirmed by pedigree analysis. Estimates of the probabilities of identical band patterns in unrelated individuals of different breeds (Swedish Trotters, North Swedish Trotters, Thoroughbreds and Arabians) were in the range 1 x 10(-4) - 7 x 10(-6). The variability derived with the (TG)n probe in horses was higher than what we obtained with several other commonly used probes for DNA fingerprinting. Individuals within breeds tended to be more similar to each other with regard to DNA fingerprint pattern than to individuals of other breeds. Moreover, a parsimony analysis made on the basis of the hybridization patterns gave clustering of individuals within breeds. The possibility of using hypervariable probes for the identification of breed-specific characters is discussed.

Animals↗
PubMed1991

Rearrangement of 9p13 as the primary chromosomal aberration in adenoid cystic carcinoma of the respiratory tract.

Two adenoid cystic carcinomas, one of the nasal cavity, the other a bronchial tumor, were cytogenetically analyzed. The former had a t(6;9)(q21-22;p 13-21) as the sole karyotypic abnormality. The latter had two related abnormal clones, resulting in the mosaic karyotype 46,XY,t(9;17)(p13;p13)/46,Y,t(X;6)(p22;q23),t(9;17)(p13;p13). The karyotypic profiles of the two cases, the only respiratory tract adenoid cystic carcinomas that have been cytogenetically characterized, differ little from those of previously reported adenoid cystic carcinomas of the major salivary glands, underscoring the fundamental biologic similarity among these tumors even when they develop from different structures and in different anatomical sites and organs. Because in the second case the t(9;17) obviously must have preceded the t(X;6), we conclude that both tumors had rearrangement of 9p13 as the primary cytogenetic change. The data thus add to the evidence that 6q changes are frequent, albeit at least sometimes secondary, aberrations in malignant salivary gland tumors. A subset of adenoid cystic carcinomas instead have rearrangement of 9p as the primary, and presumably pathogenetically essential, abnormality.

Adult↗
PubMed1991

Clonal chromosome abnormalities and in vitro growth characteristics of classical and cellular schwannomas.

Cytogenetic analysis was performed on 12 schwannomas, 10 classical and two of the cellular type. Electron microscopic examination of cultured cells from two classical and two cellular schwannomas revealed features compatible with a Schwann cell differentiation. Immunohistochemical analysis of the cultures demonstrated immunoreactivity for S-100 protein in 6 of 6 cases and for vimentin in 2 of 2 cases of classical schwannoma, thus further supporting the authenticity of the cultured cells. Cultured cells from one cellular schwannoma also exhibited immunoreactivity for glial fibrillary acid protein (GFAP). Cytogenetic analysis of the 12 tumors revealed clonal abnormalities in 10 of the cases. In the majority of tumors, cells with a normal karyotype coexisted with different abnormal clones and sporadic deviations. Numerical changes predominated and were found in all tumors, while structural rearrangements were detected in eight tumors. The most common abnormality was clonal or sporadic loss of chromosome 22, which was found in all cases. Other clonal abnormalities included loss of one sex chromosome found in five cases, -15 found in three cases, and -12, +5, +7, +20 found in two cases each. These results provide further evidence in support of a role for loss of chromosome 22 in the pathogenesis of schwannomas. Our findings also indicate that there exist several different evolutionary pathways for schwannomas, and that some of these are shared by several other types of benign and malignant tumors of the nervous system.

Adult↗
PubMed1991

Binding of herpes simplex virus to cellular heparan sulphate, an initial step in the adsorption process.

It has been suggested that heparan sulphate has a receptor function in the initial phase of the attachment of herpes simplex virus (HSV) to cells. We have studied the influence of glycosaminoglycans on cell adsorption of, and plaque formation by, HSV-1 and HSV-2, with regard to the role of saccharide structure, chain length and charge density. Heparin and highly-sulphated heparan sulphate (1.5 sulphate groups/disaccharide unit), but neither chondroitin sulphate nor dermatan sulphate, were found to compete with the cellular receptor for attachment of HSV. Heparan sulphate preparations of low sulphate content (0.5 and 0.7 sulphate groups/disaccharide unit) failed to show any significant interaction with HSV. Oligosaccharides generated by partial deaminative cleavage of heparin were used to determine the minimum molecular size required for the binding of virus; the smallest oligosaccharide which reacted with HSV was composed of 10 monosaccharide units. The importance of charge density was demonstrated more directly by subfractionation of the heparin dodecasaccharide fraction by anion-exchange HPLC. The virus-binding capacities of the four resulting dodecasaccharide subfractions increased from the least sulphated to the most heavily sulphated fraction. The results reported are discussed in relation to virus-receptor interactions involved in the attachment of HSV, including the reported binding of HSV to the fibroblast growth factor receptor.

Carbohydrates↗
PubMed1991

Caries-preventive effect of dentifrices containing various types and concentrations of fluorides and sugar alcohols.

The caries-inhibiting effect of unsupervised daily use of four different toothpastes was compared in a 3-year clinical and microbiological study: (1) 0.8% sodium monofluorophosphate (MFP) with 3% xylitol and 6% sorbitol; (2) 0.03% sodium fluoride with 3% xylitol and 6% sorbitol; (3) 0.8% MFP with 9% sorbitol, and (4) 0.03% sodium fluoride with 9% sorbitol. In all 284 children, 12-13 years old at baseline, took part in the study. After 3 years, no statistically significant differences were found between the different toothpaste groups concerning either development of initial or gross caries lesions or number of mutans streptococci and lactobacilli in saliva. However, children with no detectable approximal caries at baseline, who used the MFP toothpaste with the xylitol-sorbitol mixture, showed a lower (p less than 0.05) caries increment as compared with children who used the MFP toothpaste with sorbitol alone.

Adolescent↗
PubMed1991

[Working and living conditions of Danish medical assistant].

In spring 1988 almost 6,000 members of the Danish Association of Young Doctors answered a questionnaire containing 132 questions about their working and living conditions. The Danish study shows that many young doctors are worried by uncertain conditions of employment, lack of opportunities for further training, and demanding emergency duty. Traditional sex role patterns in the families afflict the women doctors who have difficulty in holding their own in the keen competition. Stress in different forms is regarded as a problem by about 25 per cent. Almost half of the respondents had wholly or partially regretted their choice of a career and one fifth had considered changing their profession. The physicians own occupational injuries are substantially (24 per cent) underreported. Swedish and Finnish studies indicate that the problems in the medical profession are similar in the Nordic countries.

Alcohol Drinking↗
PubMed1990

Two daily subcutaneous injections of fragmin as compared with intravenous standard heparin in the treatment of deep venous thrombosis (DVT).

In a prospective, randomized, open study 119 consecutive patients with phlebographically verified deep venous thrombosis (DVT) of the leg (36% distal and 64% proximal) were treated either with a low molecular weight heparin (Fragmin, Kabi-Vitrum) subcutaneously (120 anti-FXa U/kg) twice daily or standard heparin (SH) as continuous intravenous infusion (480 IU kg-1 day-1). The Fragmin doses were adjusted to achieve an anti-FXa activity of 0.2-0.4 U/ml before injection and not greater than 1.5 U/ml 4 h after the morning injection. The SH dose was modified to prolong the APTT 2-3 times. Repeat phlebography after 5-7 days showed improvement in 34/45 patients (76%) in the Fragmin group and in 30/49 patients (61%) in the SH group and progress in 2/45 (4%) and 3/49 (6%), respectively. The mean Marder scores decreased from 18.7 +/- 12.1 to 15.7 +/- 12.7 in the Fragmin group and from 16.9 +/- 12.0 to 14.4 +/- 11.8 in the SH group (ns). Two patients in the SH group and none in the Fragmin group had major bleedings. After 22 +/- 7 months follow up 6 rethromboses had occurred in the SH group and 4 in the Fragmin group. Postthrombotic signs and symptoms were similar in both groups. We conclude that two daily sc Fragmin doses seem as effective and safe as continuous SH in the treatment of DVT of the leg.

Adult↗
PubMed1990

Pharmacokinetics of oral noscapine.

The relative bioavailability in 20 healthy volunteers of 100 mg, 200 mg and 300 mg tablets of noscapine and 200 mg as a solution has been assessed in a four-way cross-over study, with repeated administration of the 200 mg dose to assess intraindividual variability. There was a disproportionate increase in the AUC of noscapine tablets, as a 3-fold increase in dose produced a 9-fold rise in AUC. This dose-dependency could mainly be attributed to saturable first-pass metabolism of the drug. Administration of noscapine as a solution resulted in a significantly higher maximal concentration at an earlier time-point and a higher AUC than the corresponding dose as tablets. Repeated administration of noscapine tablets and solution yielded higher AUC on the second dosing occasion. No cause for this carry-over effect was found, and the contribution of remaining noscapine was negligible. The terminal half-life of noscapine, which was independent of formulation or dose size was 4.5 h. Both inter- and intraindividual variability in noscapine kinetics were very high, e.g. 73% and 51% CV of the AUC for the 200 mg tablet.

Administration, Oral↗