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Biomedical subjects

C Ekedahl

Publications and source records attributed to C Ekedahl.

At least 19 recordsLinked to original sources

Acute epiglottitis--aetiology, epidemiology and outcome in a population before large-scale Haemophilus influenzae type b vaccination.

Over a period of 18 years 219 consecutive cases of acute epiglottitis were diagnosed and subsequently investigated in order to elucidate the aetiology, epidemiology and outcome of this disease in a well-defined population in Sweden before general vaccination against Haemophilus influenzae type b infection was introduced. Compared with the results from other parts of the industrialized world, high incidence rates were found in both children (14/100,000/year) and adults (2.3/100,000/year). The annual trend showed a significant decline in incidence among children, whereas in adults it remained unchanged. In cases where the aetiological agent could be determined, infection with H. influenzae type b was the main cause of disease in all age groups. However, in adults 27% (6/22) had a disease caused by micro-organisms other than H. influenzae type b that were verified with a blood culture. Sixty-eight per cent had a negative blood culture. The mortality rate was 0.5% (1/219) and 6% (13/219) developed a significant complication of the disease.

Acute Disease↗

Activated T cells in the nasal mucosa of patients with grass-pollen allergy. A pilot study.

Six patients with grass-pollen allergy were provoked with water-soluble grass pollen until a pronounced allergic reaction occurred. This was performed outside the grass-pollen season, and the allergen was administered on the edge of the inferior turbinate. Biopsies were taken both before provocation and during the reaction, 15-30 minutes after provocation. The nasal population of immunohistochemically positive cells for HLA-DR, CD1, interleukin-2-receptor, IgE, CD4 and CD8 were studied. There was a marked increase of IL2-R-positive cells (activated T lymphocytes) in the nasal mucosa after provocation, whilst the other cell populations approximately remained unchanged (apart from a certain increase of IgE). The increase of activated T lymphocytes may imply that certain subsets of T cells play a role in the allergic response, and that the role of helper T cells very likely is much more complex than the regulation of mast cells and eosinophils. The concomitant presence of Langerhans' cells (CD1-positive) and activated T lymphocytes may indicate a possible association on site between an antigen-presenting cell and both effector as well as memory cells in allergic reactions.

Allergens↗

Significance of the choice of tissue culture technique on the chromosomal patterns in human mixed salivary gland tumors.

Cytogenetic observations by banding methods in 56 new cases of human benign pleomorphic adenomas are reported. Thirty of the cases (series I) were studied in preparations from primary cultures established from cells growing out from mechanically dispersed tumor pieces. The remaining 26 cases (series II) were analyzed in preparations from primary cultures established from enzymatically pretreated material. The use of the latter method resulted in a decrease in the frequency of cases with a normal stemline from about 53% to about 19%. However, the general characteristics of the aberrations observed in abnormal stemlines in both series agreed well. The minor differences observed consisted of a higher frequency of recurrent t(3;8)(p21;q12) in series II and, in the same series, fewer cases showing an involvement of 8q or 12q. The present results emphasize the importance of molecular studies of, in particular, the regions 8q12, 12q13-15, and 3p21.

Adenoma, Pleomorphic↗

[Acute sinusitis in adults].

An average of 1.4% of the more than 30,000 participants in a treatment study were diagnosed as having acute sinusitis. 62% of all cases of sinusitis arose in patients aged between 15 and 44 years. Treatment with antibiotics is indicated in purulent sinusitis whilst non-purulent sinusitis is treated either with local or systemic antiphlogistic agents. The secondary bacterial infection is usually caused by Haemophilus influenzae, Streptococcus pneumoniae and anaerobic bacteria. In Scandinavia these probably account for 90% of the purulent sinusitis cases whilst Branhamella catarrhalis is responsible for the remaining 10%. Penicillin V is the agent of choice in acute sinusitis. Cefaclor is preferable in combatting H. influenzae. In a double blind study comparing doxycycline to cefaclor in the management of acute sinusitis (108 patients with cefaclor, 105 patients with doxycycline, no difference emerged between the two groups in the subjective assessment of the treatment results. Objective evaluation recorded excellent results for 88% and 83% of the patients in the cefaclor and doxycycline groups, respectively. Side-effects were noted by 7% of the cefaclor and by 13% of the doxycycline patients. The difference between the incidence of side-effects was not statistically significant. Taking into account the treatment results, the side-effects and ecological aspects, cefaclor is second only to penicillin as the agent of choice in suspected or confirmed purulent sinusitis (e. g. in presence of penicillin allergies or failure of the infection to respond to penicillin V).

Acute Disease↗

Polyclonal chromosomal evolution in a benign mixed salivary gland tumor.

Banding analyses of a human benign pleomorphic adenoma in the parotid gland revealed a polyclonal pattern where structural rearrangements predominated. These deviations were different from the anomalies previously observed in 100 mixed tumors. The reason found for the differences in all likelihood was x-ray treatment of tuberculous lymphadenitis in the neck during childhood. Implications regarding origin and development of pleomorphic adenomas are discussed.

Adenoma, Pleomorphic↗

Pharmacokinetics of phenoxymethylpenicillin in tonsils.

The pharmacokinetics of phenoxymethylpenicillin in tonsillar tissue was studied in 33 patients who underwent tonsillectomy, mainly because of repeated tonsillitis or peritonsillitis. The patients were operated on 30-240 min after an oral penicillin dose of 12.5 mg/kg body weight. The mean serum concentration was 2.8 micrograms/ml for 10 patients operated upon 80-95 min after drug administration. The mean tissue concentration for these patients at the same time was 0.6 micrograms/g. The mean concentration of penicillin in tissue after 240 min was 0.05 micrograms/g. 19% of the serum concentration was recovered in the tonsillar tissue. No significant difference between penicillin concentration in the centre or surface of the tonsils was found. The tissue concentration was calculated to be above 0.03 micrograms/ml for at least 4-5 h. 30% of the patients harboured penicillinase producing bacteria on their tonsils, mainly Staphylococcus aureus. These patients had a lower tissue concentration than those lacking the bacteria, but the difference was not statistically significant (p = 0.095).

Adolescent↗

Treatment failure in acute streptococcal tonsillitis in children over the age of 10 and in adults.

13/169 outpatients (8%) with streptococcal tonsillitis developed a new tonsillitis with the same strain within 2 weeks of completion of therapy (clinical treatment failures) and 24 (14%) remained carriers (bacterial treatment failures) after treatment with phenoxymethylpenicillin (penicillin V) 12.5 mg/kg body weight twice daily for 10 days. The mean serum concentration 60 min after penicillin V administration was 7.84 micrograms/ml. Very large individual differences in serum concentration were found but these differences could not be correlated to treatment failure. About 60% of the patients showed salivary concentrations around 0.03 micrograms/ml. Three strains of streptococci (groups C and G) from patients with bacterial treatment failure had MIC values of 0.06 and 0.12 micrograms/ml. A majority of the patients with clinical treatment failures had contact with individuals with high carrier rates of beta-hemolytic streptococci. It therefore seems likely that some so-called treatment failures in reality are new infections. In clinical treatment failures group A streptococci were twice as common as groups C + G. In bacteriological treatment failures the ratio between A and C + G was 1:1. Patients with nonstreptococcal tonsillitis as well as carriers of groups C and G may appear among bacterial treatment failures.

Acute Disease↗

Distribution of lymecycline in interstitial fluid and paranasal sinus mucosa. An experimental and clinical study.

A comparison between different methods of determining the levels of lymecycline in tissue is presented. The drug levels have been compared with those registered, during the steady state condition, in interstitial fluid obtained from subcutaneously implated tissue cages in rabbits. The 'tissue piece diffusion method' developed is reproducible; it allows antibiotic levels to be determined in minute pieces of tissues, and it seems to measure the total diffusable drug in the interstitial fluid phase. This method was employed in the analyses of lymecycline concentrations in the maxillary sinus mucosa in 12 patients, and it demonstrated a good penetration into the tissue. The level reached was well above the Minimal Inhibitory Concentration of most bacteria causing maxillary sinusitis.

Animals↗

Specificity and implications of ring chromosomes and dicentrics in benign mixed salivary gland tumours.

Among 61 human pleomorphic adenomas subjected to chromosomal study by banding methods, two rare cases were detected, one having a dicentric marker chromosome and the other a ring chromosome included in the stemline karyotype. Excepting meningiomas, such marker types have previously only been observed in different types of malignant neoplasms. However, as in meningiomas, the occurrence of dicentrics or rings has no implications as regards the question of malignancy. Both our mixed tumours showed structural changes affecting one chromosome No. 8. These findings, along with similar observations in other pleomorphic adenomas, are discussed in relation to recently advanced hypotheses about the role of oncogenes and changes of gene dosage in the genesis and/or development of mixed tumours.

Adenoma, Pleomorphic↗

Interference of alpha-hemolytic streptococci isolated from tonsillar surface on beta-hemolytic streptococci (Streptococcus pyogenes)--a methodological study.

The interference between alpha-streptococcal strains obtained from patients with repeated tonsillitis and a collection of group A streptococcal strains were studied. For this purpose three in vitro methods were designed and compared. The results obtained by a simple plating technique suitable for screening purposes were found to correlate well with those using more laborious techniques. In a limited scale some of the alpha- and beta-streptococcal combinations were tested under in vivo conditions using a tissue cage model allowing repeated sampling. In most instances agreement between the results of the in vitro and in vivo methods was registered. Several alpha-strains having inhibitory capacity to the majority of a collection of group A streptococci belonging to different serotypes were found, but also alpha-strains with an inhibitory activity restricted to few group A isolates within a certain serotype. Also beta-streptococcal strains with growth inhibiting activity towards some alpha-strains were found. As the methods were chosen to eliminate many of the unspecific inhibitory factors and the beta-hemolytic test strains showed a pattern of inhibition that varied for each of the reference alpha-strains the activity is most likely attributed to bacteriocin-like substances.

Adolescent↗

Treatment of maxillary sinusitis.

Most patients with sinusitis are treated by general practitioners. Since these doctors generally do not puncture the maxillary sinus, they can not be certain that the patient has a purulent sinus infection, which is the most important sign for determining whether or not the patient should have an antibiotic. Thus, the doctor has to rely on symptoms that are most characteristic of a purulent sinusitis. The symptoms are described and the bacteria most frequently seen in sinusitis are mentioned (Haemophilus influenzae, Streptococcus pneumoniae and anaerobic bacteria). Treatment of maxillary sinusitis should primarily consist of restoring the normal milieu within the sinus by antral puncture and lavage. Penicillin V is still the first antibiotic drug of choice, because of its effectiveness in vitro and in vivo. In therapeutic failure, aeration of the maxillary sinus is first recommended. Cefaclor, tetracyclines or trimethoprim are recommended in patients allergic to penicillins. The agents are also recommended when beta-lactamase-producing strains of H. influenzae and Branhamella catarrhalis are isolated.

Anti-Bacterial Agents↗