Biomedical subjects

J Olofsson

Publications and source records attributed to J Olofsson.

At least 73 records · Page 4Linked to original sources

PubMed1993

[Minitracheotomy].

Minitracheotomy is used most often in intensive care units for tracheobronchial suctioning, especially after major abdominal and thoracic surgery. In addition, minitracheotomy is used in emergency situations involving obstruction of upper airways. Percutaneous minitracheotomy means a coniotomy that should be performed under safe conditions. The Seldinger technique may facilitate insertion of the tube. The position of the tube has to be checked by aspiration of air. We describe a case with bleeding and intralaryngeal haematoma. Usually, however, minitracheotomy seems to be a valuable and safe therapeutic asset provided that the necessary precautions are taken.

Airway Obstruction↗

PubMed1993

Prognostic significance of epidermal growth factor receptor in squamous cell carcinoma of the maxillary sinus.

The expression of epidermal growth factor receptor (EGFR) was determined immunohistochemically in two groups of maxillary sinus squamous cell carcinomas, one with recurrences at the primary site after combination therapy with radiotherapy, chemotherapy and/or surgery and one without local recurrences. Using a four-graded scale (-, +, + +, + + +), 9 of the 10 recurrent carcinomas had a staining intensity and proportion of stained cells of + + or more. A comparable staining intensity was found in 9 of the 18 non-recurrent carcinomas. This difference is statistically significant (Fisher's exact probability test, P < 0.05). These results indicate that an increased expression of EGFR may influence the recurrence rate of squamous cell carcinoma of the maxillary sinus after combined therapy.

Aged↗

PubMed1993

Tularemia: a differential diagnosis in oto-rhino-laryngology.

Tularemia can present as an oto-rhino-laryngological disease. The clinical and radiological (CT) manifestations, diagnosis and treatment are discussed based on a case report where a patient with tonsillitis and enlarged cervical lymph nodes was admitted to the department of oto-rhino-laryngology of a hospital in Northern Norway. Francisella tularensis was isolated from the blood and there was a high titre of agglutinating serum antibodies to F. tularensis. The patient's contaminated drinking water well is the suspect source of infection.

Adult↗

PubMed1993

Laser surgery in otorhinolaryngology: a 10-year experience.

Carbon dioxide laser was introduced in ENT in the early 1970s, and is now a routine treatment modality in many departments. The CO2 laser is a non-coagulating laser and works by evaporation of the tissue. Strict safety routines are important in laser treatment. However, our experiences with laser surgery are good. In the present study of 216 patients with a total of 479 treatments, we experienced no major complications. Laser surgery should be considered a valuable surgical complement, it is, however, important to gain knowledge about its pros and cons.

Carbon Dioxide↗

PubMed1992

Investigation of the human corpus luteum by ultrasonography: a proposed scheme for clinical investigation.

The corpus luteum was investigated in 18 women undergoing hysterectomy. Preoperative ultrasonography with measurements was performed before the corpus luteum was extirpated, weighed, inspected and the diameters were measured. The concentrations of progesterone and estradiol were also determined in peripheral serum. The ultrasound pictures show that the corpus luteum has a slightly cloudy central part, which can vary from hypoechoic to hyperechoic. The peripheral part (corpus luteum 'wall') has a stronger echo and the maximal and minimal thicknesses can be measured. The results showed correlations between ultrasound measurements and anatomical measurements for wall thickness, outer diameter, inner diameter and wall area of the corpus luteum (n = 12, p < 0.02-0.0001). Moreover, all mid-luteal corpora lutea with a hypoechoic central part (five of 13 women) on ultrasound scan had a cystic central structure. Based on these findings, we suggest that an ultrasound investigation of the corpus luteum in the mid-luteal phase should use the following criteria to classify it into four types. Type a: hypoechoic central part with wall of < 3 mm; type b: hyperechoic central part with wall of < 3 mm; type c: hypoechoic central part with wall of >or= 3 mm; and type d: hyperechoic central part with wall of >or= 3 mm. The finding of a hypoechoic central region with a thin wall (< 3 mm) may indicate corpus luteal insufficiency, since significantly lower serum progesterone levels were found in women with this type of corpus luteum.

Journal Article↗

PubMed1992

Synthesis of prostaglandin F2 alpha, E2 and prostacyclin in isolated corpora lutea of adult pseudopregnant rats throughout the luteal life-span.

The ability of de novo biosynthesis of prostaglandins (PGs) in individual whole corpora lutea (CL) obtained from sterile-mated adult pseudopregnant rats on different days of the luteal phase and the post-luteolytic period was evaluated. Production of PGs, progesterone and 20 alpha-dihydroprogesterone were determined after in vitro incubation of CL extirpated from Day 2 to Day 19 after mating. A time-relationship with increased accumulation of PGs in the medium was demonstrated from 18 s to 5 h, with large increments during the first 30 min. Basal accumulation of PGs in the incubation medium was highest for 6-keto-PGF1 alpha (the stable metabolite of prostacyclin) greater than PGE2 greater than PGF2 alpha greater than thromboxane B2 (TXB2) and basal accumulation of PGF2 alpha and PGE2 measured in the medium was maximal on Day 10-11 of pseudopregnancy, concomitantly with a decline in secretion of progesterone. Addition of arachidonic acid (AA) dose-dependently increased synthesis of PGs, with absolute amounts of PGE2 greater than 6-keto-PGF1 alpha greater than PGF2 alpha greater than TXB2 and addition of 14 microM indomethacin markedly inhibited accumulation of all PGs measured. Luteinizing hormone (LH, 10 micrograms/ml) stimulated progesterone secretion on all days during pseudopregnancy, but not on the post-luteolytic Day 19. LH increased PGF2 alpha, PGE2 and 6-keto-PGF1 alpha secretion on Day 13 of pseudopregnancy by 76%, 91% and 28%, respectively, but not on the other days tested. Furthermore, stimulation of PG-synthesis by addition of AA abrogated the LH-induced progesterone accumulation markedly, but only on Day 13 of pseudopregnancy. Epinephrine (5 micrograms/ml) increased production of progesterone and also PGs, but only on Day 2 of pseudopregnancy, whereas oxytocin (100 mIU/ml) was found to be without effect on progesterone as well as PG secretion on all days tested. The results of the present study demonstrates the independent ability of the rat CL to synthesize PGG/PGH2-derived prostaglandins, including the putative luteolysin PGF2 alpha. Secondly, we demonstrate that LH and AA-induced increases in PGF2 alpha and PGE2 production during the luteolytic period, may be an autocrine or paracrine mechanism involved in luteolysis.

Animals↗

PubMed1992

Prognostic factors in oral cavity carcinomas.

This retrospective study of 176 patients with oral cavity carcinoma showed that nearly 60% of the patients presented with an advanced stage of disease. The duration of symptoms was shorter in patients with a large tumour than with a small (p less than 0.001) and in patients with metastases than in those without (p less than 0.01). Lymph node metastases were more common in large tumours (p less than 0.01), in tumours with high malignancy grading (p less than 0.05) and in non-diploid tumours (p less than 0.001). The presence of lymph node metastases (p less than 0.001), tumour size (p less than 0.01) and tumour DNA ploidy (p less than 0.005) were the only parameters that significantly influenced survival (Cox regression analysis).

Carcinoma, Squamous Cell↗

PubMed1992

Oncocytoma presenting as a choanal polyp: a case report.

Oncocytomas account for less than 1% of all salivary gland neoplasms. Histochemical methods and electron microscopy showing the large amount of characteristic mitochondria have made the definition of the tumor more precise. A solid oncocytoma originating in the nose and presenting as a choanal polyp is described. Pre- and postoperative CT scans are shown as light and electron microscopy photomicrographs. The tumor had no invasive or other malignant characteristics and was therefore classified as a benign oncocytoma.

Adenoma↗

PubMed1991

[Necrotizing sialometaplasia of the hard palate].

Necrotizing sialometaplasia is a benign, self-healing disease of salivary gland tissue and is usually confined to the minor salivary glands of the hard palate. It has clinical and histological features that simulate malignancies such as mucoepidermoid and squamous cell carcinomas. Wrong diagnosis has led to unnecessary mutilating surgical procedures. The etiology of the disease is unknown, but an ischaemic process is considered most likely. We describe two patients with necrotizing sialometaplasia, one with midline and one with bilateral symmetrical affection of the hard palate.

Adult↗

PubMed1991

Human respiratory mucosa in a nonadhesive stationary organ culture system.

Fragments of human adenoid tissue were transferred to a nonadhesive, stationary organ culture system. The culture period was 40 days. In culture, beating cilia could be observed at the surface of the fragments. Light microscopy, scanning electron microscopy, and transmission electron microscopy showed that the tissue fragments were covered by a multilayered, pseudostratified, ciliated epithelium. Beneath the epithelium was a basement membrane. At the start of the culture period, the central parts of the fragments were dominated by lymphocytes. These lymphocytes gradually disappeared and were replaced by a collagen-containing stroma with scattered fibroblasts. The tissue fragments can be used as an organ culture model for normal respiratory mucosa.

Adenoids↗

PubMed1991

Protein phosphorylation substrates in normal and neoplastic squamous epithelia of the human upper aero-digestive tract.

Protein phosphorylation was studied in crude and in protein kinase C (Pk-C)-enriched preparations from squamous cell carcinomas and normal mucosa of the human upper aero-digestive tract. In crude soluble preparations from neoplastic mucosa we found a 5-fold higher basal endogenous phosphorylation when compared to normal mucosa. In particulate fractions the increase was 3-fold. SDS-PAGE and autoradiography of phosphorylated proteins in crude soluble tumor extracts showed bands corresponding to proteins with apparent molecular weights of 18, 37, 40-42, 52, 60, 62 and 90 kDa. In normal mucosa the phosphorylation of these proteins was very low or absent, except for the proteins with molecular weights of 40-42 and 52-55 kDa. Addition of Ca2+ or Ca2+/phospholipids to the reaction mixture caused phosphorylation of additional proteins with apparent molecular weight of 45-50 kDa in soluble preparations of tumors. Cyclic AMP or cGMP had no significant effect on the phosphorylation of endogenous proteins. In the partially purified, Pk-C-enriched fractions the phosphorylation in the presence of Ca2+/phospholipids was distinctly higher in tumors when compared to the phosphorylation observed in normal mucosa, and some phosphorylation substrates were detected only in tumor tissue. In order to find out whether the elevated basal phosphorylation was due to an endogenous activation of protein kinases, different inhibitors of serine/threonine protein kinases were tested. These inhibitors included: heat-stable cyclic AMP-dependent protein kinase (Pk-A) inhibitor, Pk-A inhibitor peptide (Wiptide), heparin and the Pk-C inhibitors peptide 19-36 and H-7. None of these inhibitors had any significant effect on the basal phosphorylation. In conclusion, our results show the existence of endogenous phosphorylation substrates in human squamous cell carcinomas from the upper aerodigestive tract, and indicates that there is a significantly higher basal and Pk-C specific phosphorylation of endogenous substrates in tumors compared to normal mucosa. This may be of importance for the transformation and altered growth regulation in epithelial tumors.

Aged↗

PubMed1991

Regulation of prostaglandin biosynthesis by luteinizing hormone and bradykinin in rat preovulatory follicles in vitro.

Luteinizing hormone (LH) stimulates prostaglandin biosynthesis and steroidogenesis in preovulatory (PO) follicles prior to ovulation. Since the ovulatory process shares many similarities with an inflammatory reaction, mediators of the inflammatory response, such as bradykinin (BK) have been suggested to modulate the effects of LH. In the present study the effect of BK (5 microM) on: 1) prostaglandin biosynthesis (PGE2, PGF2 alpha and 6-keto-PGF1 alpha), 2) the levels of two enzymes in the cyclo-oxygenase pathway, prostaglandin endoperoxide synthase (PGS) and prostacyclin synthase (PCS), and 3) cyclic adenosine 3'5'-monophosphate (cAMP) and progesterone response of PO follicles incubated in vitro were examined. LH (0.1 microgram/ml) stimulated the accumulation of cAMP and progesterone in the medium, while BK had no effect on these parameters. BK exerted a slight stimulatory effect on PGE2, and PGF2 alpha, (p less than or equal to 0.01) but not on 6-keto-PGF1 alpha synthesis, but no changes in PGS or PCS levels could be detected. The effect of LH on prostaglandin biosynthesis was much more pronounced, with an increase of PGE2, PGF2 alpha and 6-keto-PGF1 alpha. LH also induced PGS. The combination of LH and BK did not alter these responses compared to that of LH alone. This study demonstrates that BK stimulates prostaglandin biosynthesis in PO follicles. In contrast to LH, this effect of BK does not seem to involve the adenylate cyclase system, since BK did not stimulate cAMP production. BK did not affect the levels of PGS or PCS, and the stimulatory effect of BK is suggested to involve an increase in the availability of substrate for the cyclo-oxygenase pathway.

Animals↗

PubMed1991

Heterogeneity of squamous cell carcinomas of the oral cavity studied by flow cytometry.

The DNA pattern was determined by flow cytometry in 76 samples from 16 squamous cell carcinomas of the oral cavity to assess intratumour DNA heterogeneity. Heterogeneous DNA content was found in 2 tumours (12%); both containing DNA diploid and DNA aneuploid cell clones. The remaining 14 tumours showed a homogeneous DNA distribution in the different specimens; 9 (56%) were diploid, 3 (19%) aneuploid and 2 (12%) were polyploid. The DNA non-diploid tumours were clinically more advanced than the DNA diploid ones (p less than 0.05). The tumour proliferation rate (fraction of cells in S-phase) was higher in aneuploid tumours than in diploid ones (p less than 0.01).

Adult↗

PubMed1991

Stimulatory effects of bradykinin on the ovulatory process in the in vitro-perfused rat ovary.

The role of bradykinin in the ovulatory process was investigated using an in vitro-perfused rat ovary model. Stimulation with LH (0.1 micrograms/ml) resulted in 2.6 +/- 0.5 (mean +/- SEM) ovulations per ovary, whereas no ovulations occurred in the nonstimulated control group. Bradykinin (5 microM) added to the perfusion system hourly for 10 h induced 2 of 5 ovaries to ovulate, with 2 and 3 ovulations, respectively. When bradykinin (5 microM) was given as a single dose at 5 or 10 h after LH, the ovulation rate was significantly increased to 11.0 +/- 2.8 and 8.6 +/- 2.0 ovulations per ovary, respectively. A competitive bradykinin antagonist, phenylalanine bradykinin, inhibited the bradykinin-induced increase in LH-stimulated ovulations. The addition of LH, but not of bradykinin, increased the levels of prostaglandin endoperoxide synthase in granulosa cells, but the levels of the enzyme in the residual ovarian tissue were negligible. In contrast, prostacyclin synthase was predominantly located in the residual ovarian tissue. This enzyme was not affected by LH or bradykinin. LH increased the tissue levels of prostaglandins, predominantly prostaglandin E2 (PGE2), at 7 h, whereas the stimulatory effect of bradykinin was smaller, with a preferential increase in prostacyclin (prostaglandin I2) levels. This study indicates a modulatory role of bradykinin, possibly involving prostacyclin late in the ovulatory process, in the rat.

Animals↗

PubMed1991

Oesophageal speech after laryngectomy: a study of possible influencing factors.

52 patients with laryngeal carcinoma were studied before and after laryngectomy with regard to what factors might influence the development of oesophageal speech. The investigations consisted of oesophageal manometry, a follow-up interview and a review of surgical approaches and radiotherapy. 43% of the patients achieved socially acceptable oesophageal speech, 22% were able to speak single words, and 35% had no oesophageal speech at all. 61% had post-operative dysphagia. Age was the only factor which significantly correlated to intelligible speech. The intraoesophageal pressure during oesophageal phonation exceeded in all cases the low PO-HPZ pressure after operation. The extension of surgery and radiation field, severity of dysphagia, alcohol and smoking habits, and mental condition did not differ between the 3 groups of oesophageal speech. It was concluded that the rather complicated process of acquiring oesophageal speech is much more dependent on learning ability which decreases with age than on various kinds of motor dysfunction after laryngectomy.

Adult↗

PubMed1991

Expression of epidermal growth factor receptor in glottic carcinoma and its relation to recurrence after radiotherapy.

The expression of EGFR was determined immunohistochemically in two groups of patients with glottic carcinoma, one that recurred after a full course of radiotherapy and one that did not. Using a 4-graded scale (-,+,++, ) 80% (12/15) of the recurrent carcinomas had a staining intensity and proportion of stained cells of ++ or more. The same figure for non-recurrent carcinomas was 39% (7/18). The difference is statistically significant (chi-squared with Yates' correction, P less than 0.05). The results indicate that an increased expression of EGFR may influence the rate of recurrence of glottic squamous cell carcinoma after radiotherapy.

Aged↗

PubMed1991

Immunohistochemical study of epidermal growth factor receptor in severe dysplasia and carcinoma in situ of the vocal cords.

The presence of epidermal growth factor receptor (EGFR) was studied in laryngeal biopsy specimens from 14 patients, all with severe dysplasia or carcinoma in situ. All 14 cases showed positive immunoreaction for EGFR. In 5 of the specimens there were also areas with moderate dysplasia, 3 of which showed scattered EGFR positive cells, whilst 2 were negative. In 8 biopsy specimens there were areas with mild dysplasia, but none of them showed any positive immunoreaction for EGFR. Thus EGFR is present in laryngeal severe dysplasia and carcinoma in situ, indicating the potential malignant neoplastic nature of these lesions. The immunostaining for EGFR may be used as an aid to differentiate between severe dysplasia and carcinoma in situ (Group III lesions), moderate (Group II lesions) and mild dysplasia (Group I lesions).

Biopsy↗

PubMed1991

Tyrosine kinase activities in normal and neoplastic epithelia tissue of the human upper aero-digestive tract.

Tyrosine kinase activity was studied in the crude cytosolic and particulate fraction of normal mucosa and squamous cell carcinomas of the upper aero-digestive tract. In the presence of exogenously added phosphorylation substrate (Glu,Tyr4:1), the cytosolic tyrosine kinase activity was 6-fold higher in tumors compared to normal mucosa (p = 0.001), and in the particulate fraction the increase was 8-fold in tumors compared to normal mucosa. Different proposed tyrosine kinase inhibitors, including genistein, quercetin and the alpha-cyanocinnamide ST 638, were tested for their ability to inhibit phosphorylation of the synthetic tyrosine phosphorylation substrate. Phosphorylation of Glu,Tyr4:1 in tumors (cytosolic fraction) was reduced to 77.8 +/- 8.7% of the control value by 10 microM ST 638 (p less than 0.05), and to 50.7 +/- 10.4% by 100 microM quercetin (p less than 0.01). In normal mucosa (cytosolic fraction) the corresponding values were 41.7 +/- 16.6% in the presence of 10 microM ST 638 (p less than 0.05) and 32.1 +/- 5.8% in the presence of 100 microM quercetin (p less than 0.05). These inhibitors had no effect on the tyrosine kinase activity in the particulate fractions. Phosphorylation of endogenous proteins in the crude cytosolic fraction was evaluated by SDS-polyacrylamide gel electrophoresis after alkali treatment of the gels. Autoradiography of the gels treated in this manner revealed bands corresponding to phosphorylated proteins with apparent molecular weight of 18, 23, 37-38, 42-44 (double band), 53-55 (double band), 61 and 92-94 (double band) kD. Quercetin (100 microM) markedly reduced the phosphorylation of these proteins, while no effect of ST 638 could be seen. Heparin (20 micrograms/ml) stimulated the phosphorylation of three proteins with apparent molecular weight of 39 and about 72 kD, respectively, and inhibited the phosphorylation of 2 proteins with molecular weight of 92 and 53 kD in tumors. These features were observed in both tumors and normal tissue, with the exception that heparin only stimulated the 72 kD band in normal mucosa and that the phosphorylation was markedly higher in tumors. In summary, our results show an increased tyrosine phosphorylation in squamous cell carcinomas of the upper aero-digestive tract compared to normal oral mucosa. These differences and their origin might be of vital importance in the regulation of events leading to malignant transformation.

Aged↗