Claes Ekedahl

The mixed salivary gland tumor — A normally benign human neoplasm frequently showing specific chromosomal abnormalities☆

Abstract Using banding techniques, 10 pleomorphic adenomas were studied in preparations from primary cultures. Forty per cent of the tumors had one or more abnormal stem lines. Two of the benign mixed tumors showed an identical and reciprocal 3;8 translocation. A third adenoma, with signs of early malignant transformation, had a 3p− marker and a 8p−q− marker with break points close to those found in the two cases with identical 3;8 translocation. The fourth adenoma with an abnormal stem line contained as many as 8 different markers in its stem line karyotype; the findings in this case—where there was no involvement of Nos. 3 and 8—showed that several, possibly many, karyotypic evolutionary pathways exist in pleomorphic adenomas. The results are discussed in relation to the previously existing sparse data available on mixed tumors and in relation to the possible general significance of chromosome changes affecting Nos. 3 and 8.

Recurrent chromosomal aberrations in non-Hodgkin and non-Burkitt lymphomas

Abstract Eleven non-Hodgkin and non-Burkitt type lymphomas were studied in direct preparations with banding techniques. The results from these experiments and those from 13 cases reported earlier were surveyed, together with data from 64 additional cases from the literature. A great number of recurrent deviations, particularly structural ones, were revealed: 1) A 14q+ marker was found in 45% of the cases; the extra material was derived from 11 different chromosome types (usually from their long arms) and translocated onto No. 14 at q32; Nos. 1, 8, 10, 11, 14, and 18 were involved as donor chromosome more than once, i.e., in 5, 5, 2, 6, 3, and 5 cases, respectively; for each recurrent donor chromosome the same, or almost the same, segment was translocated in different cases. 2) A 6q− marker with break points in q21 – 23 or q13 – 15 was observed in up to one-quarter of the lymphomas. 3) Other common recurrent marker chromosomes were 1q−, 11q−, 1q−, 9q−, 18q−, 3p−, and 8q−. 4) A gain of one No. 3 was a frequent, and often early, change in abnormal stem lines; other common numerical deviations were gains of Nos. 7 and 18 and losses of Nos. 8 and 15. It is hypothesized that the distribution and characteristics of recurrent deviations, particularly structural ones, are “programmed” by genic changes related to cell differentiation.

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.

Quantitative Measurement Of Drooling

A method for quantitative measurement of drooling, utilizing the radioactive isotope 99mtechnetium, is introduced. The aim of this method is to evaluate results of therapy against this state. Drooling patients were given 100 μCi 99mTC intravenously. Saliva samples were repeatedly taken from the mouth for 9 hours and the isotope concentration was examined. The drooled saliva was collected in disposable bibs. From the measured radioactivity in the bibs and the saliva samples, the amount of drooled saliva could be calculated. The results show, as regards saliva production in a normal population, great variations in amount of drooled saliva within as well as between individuals. With due precautions, the method is useful for quantitative measurement of drooling.

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.

Interference of α-hemolytic streptococci isolated from tonsillar. Surface on β-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.

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).

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.

Active Phenoxymethylpenicillin (Pcv) in the Mucous Membranes of the Oral Bucca and Maxillary Sinus and in Diffusion Chambers Implanted in Rabbits: A Methodological Study

The intention of prescribing antibiotic treatment must be to achieve a concentration of the agent within the infected tissue well above th MIC or the bacteria causing the infection. As a basis for further clinical studies on antibiotic concentrations in maxillary sinus mucosa in humans, determinations of biologically active penicillin V in the mucous membranes of the maxillary sinus and the buccal mucose as well as in tissue fluids and tissue from subcutaneously implanted tissue cages in rabbits were made. Several experimental conditions were studied, with the purpose of establishing optimal conditions with regard to tissue sampling, blood contamination, prediffusion time, etc. Penicillin V was shown to have a good penetration into mucosal tissue in the rabbit, even at low perfusion pressure.

Experimental Tracheal Wall Injury

A plan for experimental analysis of tracheal wall injuries in rabbits is presented. Preliminary results after different types of injuries to the tracheal mucouse are given.