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Biomedical subjects

M Eriksson

Publications and source records attributed to M Eriksson.

At least 343 records · Page 19Linked to original sources
PubMed1988

Binding geometries of benzo[a]pyrene diol epoxide isomers covalently bound to DNA. Orientational distribution.

Flow linear dichroism (LD) of different benzo[a]pyrene diol epoxide (BPDE) isomers covalently bound to calf thymus DNA or poly(dG-dC) provides information about binding geometry and DNA perturbation. With anti-BPDE the apparent angle between the long axis (z) of the pyrene chromophore and the DNA helix axis is approximately 30 degrees as evidenced from the LD of z-polarized absorption bands in the pyrenyl chromophore at 252 and 346 nm. The corresponding angle for the in-plane short axis (y) is determined to be approximately 70 degrees from a y-polarized band at 275 nm. The binding of (+)-anti-BPDE to DNA is found to cause a considerable reduction of the DNA orientation. This is ascribed to a decreased persistence length of DNA, owing either to increased flexibility ("flexible joints") or to permanent kinks at the points of binding. The reduced linear dichroism (LDr), i.e., the ratio between LD and isotropic absorbance, of the long-wavelength absorption band system of BPDE bound to DNA exhibits a wavelength dependence that indicates a relatively wide orientational distribution of the z axis of pyrene. Fluorescence data support the conclusion of a heterogeneous distribution, and a very low polarization anisotropy indicates a mobility between the different orientational states, which is rapid compared to the fluorescence lifetime (nanosecond time scale). Attempts are made to simulate the observed LDr features of the (+)-anti-BPDE-poly(dG-dC) complex using different distribution models on the assumption that the angular dependence of the spectral perturbation is due to dispersive interactions with DNA bases.(ABSTRACT TRUNCATED AT 250 WORDS)

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗
PubMed1988

Pharmacokinetics of streptomycin in Ethiopian children with tuberculosis and of different nutritional status.

Fifty-six malnourished Ethiopian children with tuberculosis classified in four nutritional groups (normal, underweight, marasmus and kwashiorkor), were given streptomycin 20 or 30 mg.kg-1 i.m. The plasma concentration-time data revealed an increased apparent volume of distribution in children with kwashiorkor compared to normals. The total plasma clearance was low and did not differ between the nutritional groups. Thus, the half-life was prolonged only in kwashiorkor. The results could be explained by decreased protein binding in plasma and decreased renal clearance by glomerular filtration.

Child↗
PubMed1988

Predictive indicators for adjustment in 4-year-old children whose mothers used amphetamine during pregnancy.

Psychosocial factors that could be used as predictive indicators for adjustment of 4-year-old children whose mothers had used amphetamine during pregnancy were studied by means of simple and multivariate correlation analyses. The following statistically significant correlations were found: Length of maternal alcohol and drug abuse during pregnancy was correlated negatively with the child's adjustment as were numbers of paternal criminal convictions, number of stress factors of the mother, and number of earlier children born to the mother. Paternal criminality was associated with the outcome, regardless of amount of contact between father and child.

Amphetamine↗
PubMed1988

Efficacy and safety of cefpirome (HR810).

Sixty adult patients with suspected systemic bacterial infections were treated with cefpirome 1 g or 2 g twice daily for 5-22 days. Forty-seven patients were evaluable for clinical efficacy. Diagnoses in evaluable patients were urinary tract infections (20), pneumonia (10), soft tissue infections (17), and bone and joint infections (4); four patients had two infections each. Nine patients were bacteraemic and all were cured; the responsible bacteria were Escherichia coli (6), Streptococcus pneumoniae (1), Pseudomonas aeruginosa (1), and Haemophilus influenzae (1). One patient with a soft tissue infection failed to respond clinically to cefpirome. Bacteriologically, 41 of 48 isolated pathogens (85%) were eradicated. In wound cultures, three strains of Staphylococcus aureus and one each of Ps. aeruginosa and Str. faecalis persisted. One Enterobacter sp. relapsed in urine. Of isolated strains, only Str. faecalis and methicillin resistant Staph, epidermidis were resistant to cefpirome. Staph, aureus strains were inhibited in vitro by 0.25 to 2 mg/l of cefpirome in agar dilution. Adverse effects, probably or possibly related to cefpirome, were skin reactions (3), fever (1), Clostridium difficile diarrhoea (2), and disturbed taste sensation (1). Tolerance was good. Cefpirome is suitable for large-scale comparative trials.

Adult↗
PubMed1988

Anaphylaxis and angioedema due to rubber allergy in children.

Delayed hypersensitivity to rubber chemicals is well known but there are an increasing number of case reports on an immediate type of hypersensitivity inducing contact urticaria and anaphylaxis in adults. We now report on three atopic children who developed angioedema, which in two of them progressed to anaphylaxis after exposure to natural rubber products. All three patients showed positive skin prick tests and one had a positive RAST test to latex from the rubber tree (Hevea brasiliensis). It is clear that sensitized subjects are at risk of developing anaphylaxis when exposed to natural rubber products, e.g. during medical examination or surgery when rubber gloves are used.

Adolescent↗
PubMed1988

Risk factors for occasional and recurrent wheezing after RSV infection in infancy.

Sixty-seven children who were hospitalized with a verified RSV infection were reexamined after 4 years at the age of 4 to 7 years. Twenty-four children had had no subsequent respiratory symptoms, 22 had wheezed 1-3 times and 21 had recurrent wheezing. A family history of atopy and a personal history of neonatal respiratory problems were more common in the group with recurrent wheezing, whereas paternal smoking was more frequent in the group with occasional wheezing. RSV infection in early infancy was more related to occasional wheezing than recurrent episodes. The spirometric data obtained from the force expirograms were normal, compared to the predicted normal values. In the children with recurrent wheezing, however, the values for PEF and the MEF25 were significantly lower in comparison with all the other children showing a mild obstruction.

Child↗
PubMed1988

Sensitization of children in the Stockholm area to house dust mites.

Atopic sensitization of children in the Stockholm area to house dust mites (HDM) was investigated in a case-control study. Sixty children with and 60 without positive skin prick tests for HDM were matched for age and sex. HDM-sensitized children had previously more often lived in other areas known to be mite infested than the control children. Sensitization to mites was related to dampness in the homes, but no significant relationship was found to the type of residence, frequent visits to a summer house in the archipelago or parental smoking. Dust samples from mattresses of the children with the strongest positive reactions to mites in skin prick tests and the respective controls were subjected to an enzyme immunoassay, to measure the content of the major allergens of the Dermatophagoides (D.) species D. pterinyssinus, D. farinae and D. microceras. Mattress dust samples from the beds of HDM-sensitized children contained significantly higher HDM antigen concentrations than those from the beds of controls. Private houses contained significantly more HDM antigens than flats and 10 of 11 homes in which a dampness problem was recognized contained mite antigens. It is postulated that mite infestation is increasing in the area, energy-saving measures creating improved conditions for HDM survival.

Adolescent↗
PubMed1988

INH and streptomycin in Ethiopian children with tuberculosis and different nutritional status.

The plasma concentration of INH and streptomycin was followed in 45 Ethiopian children with tuberculosis. The children were grouped according to their nutritional status as normal, underweight, marasm and kwashiorkor. INH was well absorbed in all nutritional groups to give therapeutically active plasma levels. When terminal half life (t1/2) of INH was calculated for individual patients there were more children in all nutritional groups with t1/2 greater than or equal to 2 hours than less than 2 hours, indicating a slow acetylation of INH. Streptomycin was well absorbed in all nutritional groups and therapeutic levels were obtained with 20 mg/kg i.m. After 30 mg/kg i.m. of streptomycin kwashiorkor children had an increased t1/2 of streptomycin indicating a decreased renal excretion of the drug in kwashiorkor. The clinical follow-up of the children indicated that serious tuberculosis could be successfully treated with INH and streptomycin in the doses used.

Child↗
PubMed1988

Shiga-like toxin production and connective tissue protein binding of Escherichia coli isolated from a patient with ulcerative colitis.

A 15-year-old girl with her first relapse of ulcerative colitis was treated with salicylazosulfapyridine, steroids, metronidazole and parenteral nutrition for 4 weeks without significant improvement. Her faecal specimens were negative for established intestinal pathogens, but strains of Escherichia coli producing Shiga-like toxin and expressing binding of fibronectin and collagen were repeatedly isolated. Neutralizing antibodies to Shiga-like toxin were detected in serum samples. Improvement was achieved during treatment with mecillinam to which the E. coli strains were sensitive.

Adolescent↗
PubMed1987

Plasma levels of gastrin, somatostatin, and cholecystokinin immunoreactivity during pregnancy and lactation in dogs.

Plasma levels of gastrinlike, somatostatinlike, and cholecystokininlike immunoreactivity were determined by radioimmunoassay in peripheral blood from 11 beagles during pregnancy and in response to suckling during lactation. Cholecystokinin was determined in pooled and in individual plasma samples after separation of cholecystokinin and gastrin by high-performance liquid chromatography. Gastrin and somatostatin levels were significantly increased during the 8-wk-long dog pregnancy; peak values were recorded in week 7 and week 4, respectively. The cholecystokinin level rose and peaked at week 3, and remained elevated. In response to suckling, maternal gastrin levels rose significantly when tested in week 1 and 3 of lactation. Somatostatin levels did not respond significantly to suckling, but basal levels were elevated in week 1 compared to week 3 of lactation. Cholecystokinin rose in response to suckling both in week 1 and 3 of lactation. We suggest that the increased levels of gastrointestinal hormones during pregnancy and lactation may serve to increase digestive and anabolic capacity.

Animals↗
PubMed1987

A sandwich ELISA for bovine serum in viral vaccines.

A double antibody sandwich ELISA for the detection of bovine serum in viral vaccines was developed and standardized with commercially available reagents. The detection limit by ELISA was 0.5 ng ml-1. ELISA was found to be 50-400 times more sensitive than the currently used assays. It was concluded that ELISA is a specific, sensitive and reproducible method for the determination of residual amounts of bovine serum in viral vaccines.

Animals↗
PubMed1987

The influence of khat-chewing on birth-weight in full-term infants.

The leaves of the shrub Catha edulis (khat) are widely chewed as part of social life in several countries around the Red Sea and in East Africa. The leaves possess stimulant properties and are also used by pregnant women. The effect of khat on birth-weight has been studied, It was found that healthy full-term, singletons, born after uneventful pregnancies and deliveries, had a significantly lower average birth-weight when the mothers were khat-chewers, either habitually or occasionally (P less than 0.001). Khat-chewing appears to be one of several maternal practices adverse to the fetus.

Birth Weight↗
PubMed1987

Spectroscopic studies on double-stranded poly d[(G-C)(G-C)] in B and Z form after covalent modification with the anti diastereomer of trans-7,8-dihydroxy-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene.

Poly d[(G-C)(G-C)] in B or Z conformation has been incubated with the anti-diastereomer of trans-7,8-dihydroxy-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (anti-BPDE). Enzymatic hydrolysis, circular dichroism (CD) and light absorption were used to study the binding specificity of anti-BPDE to the right- and left-handed forms of poly d[(G-C)(G-C)]. The effect of anti-BPDE binding on the conformational transition, induced by MnCl2 or NaCl, was also studied. The results obtained demonstrate that in Mn2+-containing solutions, when the ionic conditions are identical, there is only a minor difference in the extent of covalent binding of anti-BPDE to the polynucleotide in right- or left-handed form. A high degree of enantioselectivity of poly d[(G-C)(G-C)] towards (+)-anti-BPDE was observed with both conformational states, although the B form seems to be slightly more selective. With either form, the major adduct in the h.p.l.c. analysis is consistent with trans-N2-10-[(7 beta,8 alpha,9 alpha-trihydroxy-7,8,9,10- tetrahydrobenzo[a]pyrene)-yl]-deoxyguanosine [(+)-anti-BPDE-N2-dG] adducts. A 3 nm bathochromic shift of the light absorption of the pyrene chromophore was observed for the Mn2+-induced left-handed form of the polynucleotide. A similar shift was observed with the NaCl-induced transition only at intermediate NaCl concentrations, where the CD spectra showed a mixture of right- and left-handed forms. The bathochromic shift may be a consequence of a reduced exposure of the chromophore to the aqueous solvent. In poly d[(G-C)(G-C)] modified with anti-BPDE, higher ionic strengths are required to reach optimal B-Z transition compared to unmodified samples. This indicates that there is a restriction in the transition process at the sites of modification. The results have been discussed in terms of two distinct domains in the modified polynucleotide: one 'normal' domain, where an initially rapid transition takes place, and another 'BPDE-domain' involving the modification site and a few adjacent base pairs. It is likely that this domain is associated with the inhibitory effect on the B-Z transition.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗