Search PubMed⌕ Search

Biomedical subjects

C Lindqvist

Publications and source records attributed to C Lindqvist.

At least 181 records · Page 10Linked to original sources
PubMed1986

Autogenous costochondral grafts in temporo-mandibular joint arthroplasty. A survey of 66 arthroplasties in 60 patients.

A clinical study of 60 patients who underwent 66 costochondral arthroplasties during the period 1969-1984 is presented. In nearly half of the cases ankylosis was the main indication for operation, followed by dysplasia, tumours and osteomyelitis. The results showed that all cases in which the rib was decorticated to fit into the mandible as an inlay healed well. The mean time of IMF was 3.5 weeks. In the majority of the patients (67%) the postoperative function of the mandible was considered to be good or excellent, and nearly all patients were pain free. There were no postoperative chest infections and only one case of pneumothorax. Motor and sensory disturbances in the lower lip were each diagnosed in ten per cent of the patients.

Adolescent↗
PubMed1986

Induction of concanavalin A dose-dependent T-cell growth factor production by insertion of T-cell membrane components into the AKR thymic lymphoma BW 5147.

Sendai virus vesicles were used as vehicles for the insertion of various cell membranes into different cell lines. The transplantation efficiency was measured by using FITC-labelled concanavalin A (Con A) or monoclonal antibodies against the T-cell marker Lyt 2 and the major histocompatibility complex product H-2Db in a fluorescence-activated cell sorter. Results indicate that it is possible to transplant mitogen responsiveness to certain cell types. Con A stimulation of T-cell membrane transplanted BW 5147 showed that it is possible to induce a mitogen dose-dependent T-cell growth factor production. Consequently this method appears to be an attractive model for further study of the properties of the membrane structures involved in mitogen triggering of cells.

Animals↗
PubMed1986

A T-helper cell x Molt4 human hybridoma constitutively producing B-cell stimulatory and inhibitory factors.

A human T-T hybridoma clone with helper cell phenotype was established from fusions between a HPRT- variant of the human T-cell lymphoma Molt4, and PPD-activated normal human T-lymphocytes. The hybrid clone (MP-6) was characterized with regard to expression of markers and lymphokine secretion. The T-T hybridoma was positive for Leu 3a, and thus of T-helper cell lineage. The transferrin receptor (T-9) and the interleukin 2 (IL-2) receptor (Tac) were also expressed as judged by immunofluorescence analysis using monoclonal antibodies. The hybridoma produces B-cell stimulatory factor (BSF) with proliferation and maturation activities, growth inhibitory factor (GIF), leukocyte migration inhibitory factor (LIF) constitutively under serum free conditions, but no detectable interferons (IFN-alpha, IFN-beta, IFN-delta), nor interleukin 2 (IL-2). Weak interleukin 1 (IL-1)-like activity was found. The B-cell stimulatory factor (BSF) induced solid phase-anti-mu triggered resting B-cells obtained from human spleen, tonsil or peripheral blood to proliferate and to secrete IgM and IgG. Without anti-mu triggering the BSF had no proliferation inducing effect. The BSF was characterized and partially purified using ammonium sulphate precipitation, Blue-Sepharose, HPLC hydrophobic interaction and HPLC gel filtration chromatography. The BSF was heat labile at 56 degrees C and was present in two forms, one with high and one with intermediate hydrophobicity. The more hydrophobic form of BSF has a molecular weight of 12K-14K. Kinetic studies of the lymphokine secretion revealed that BSF was produced in detectable amounts in low density (0, 2 X 10(6) cells/ml) 18-24 h cultures. In 48 h to 72 h cultures there was a significant influence of growth inhibitory activities (GIF) produced. GIF, with an apparent MW of 90K could be absorbed out on certain tumor cell lines or on Blue-Sepharose. Further absorption analysis of BSF activities show that anti-mu triggered B-cells but neither resting B-cells nor T-cells could absorb BSF activity.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1986

Dissection technique for cochleas prepared for scanning electron microscopy.

Scanning electron microscopy (SEM) permits a three-dimensional study of the surface morphology of the organ of Corti that is very useful in evaluating the condition of the apical end of the hair cells and the stereocilia. However, some laboratories have experienced problems with curling of the basilar membrane during critical point drying of cochlear specimens prepared for SEM evaluation using the Murakami or osmium thiocarbohydrazide-procedures. This curling of the basilar membrane can obstruct the view of the reticular lamina and the ciliary ends of the hair cells. We have used a dissection method, referred to as the anchor technique, to overcome basilar membrane curling. This technique removes all the structures above the reticular lamina but leaves the basilar membrane attached to the spiral ligament and the lateral bone to which the spiral ligament is anchored. Individual cochlear turns are dissected in this manner and mounted on the same examination stub for SEM evaluation. Maintenance of the lateral attachment of the basilar membrane requires additional dissection time but eliminates the problem of curling during critical point drying. An additional benefit is that mounting the individual turns on the same examination stub facilitates evaluation and photomicroscopy of the surface morphology. The anchor technique has been used successfully on the guinea pig and should be appropriate for most mammalian cochleas.

Animals↗
PubMed1983

Tetracycline induced esophageal ulcers. a clinical and experimental study.

Medication with oral drugs has not been considered as a cause of esophageal lesions in the general literature of esophageal disease. This study demonstrates 40 patients with complaints of sudden onset of intense retrosternal pains and odynophagia during treatment with oral tetracyclines. All patients had distinct circumferential ulcers in the esophagus. Medical history, barium swallows, esophagoscopy, biopsies and esophageal manometry revealed no other apparent etiology but a local corrosive effect of the tetracyclines. Experimental tests on the esophagus of the cat verified a severe local corrosive effect of the tetracyclines. Another tetracycline, lymecycline, not reported previously to induce esophageal lesions in man, was significantly less ulcerogenic than doxycycline and oxytetracycline. Drug induced esophageal ulcerations are likely to be more numerous than previously suspected. The experimental model used appears to be sound for investigating ulcerogenic potentials of orally administered drugs.

Adolescent↗
PubMed1981

Occupations with low risk of lip cancer show high risk of skin cancer of the head.

The standardized morbidity ratios (SMR) of lip and non-melanomatous skin cancer (basal-cell carcinoma excluded) of the head and neck in males were determined for different occupational groups in Finland. The data on all cases of these types of cancer diagnosed in Finland in the age group 35-69 years in 1971-75 were supplemented by information on occupations from the 1970 census (Central Statistical Office of Finland). The expected numbers of cases were based on the age and occupation-specific numbers of person-years computed by the Central Statistical Office, and the age-specific incidence rates of lip and skin cancers among the economically active population. The highest SMR of lip cancer among all the occupational groups was found in agriculture, forestry and fishing (1.64). In contrast, the SMR of skin cancer was not higher than expected in occupations related to agriculture and forestry. Significantly lower than expected risks of lip cancer were observed among highly educated white-collar workers, among whom the risk of contracting skin cancer was the highest (technical, scientific, humanistic and artistic work, SMR 1.78). The morbidity of both lip and skin cancers varies considerably by occupation, and the risks seem to be, at least in part, inversely related. Thus, it is probable that there are also differences in the risk factors, contrary to several earlier suggestions. The nature of these factors are discussed.

Adult↗
PubMed1980

Is upper lip cancer "true" lip cancer?

A description is given of the occurrence of upper and lower lip cancers in Finland in the period 1953-1974 with the aim of reaching conclusions on the possible differences in the etiological factors involved. Substantial differences with respect to various epidemiological parameters, such as incidence rates, trends in the incidence with time, male/female ratios of the incidence rates, age-incidence curves, urban/rural ratios of the incidence rates, and geographical distribution, were demonstrated between upper and lower lip cancers. On the other hand, similarities in the occurrence of upp]er lip cancer and non-melanomatous skin cancer of the head and neck could be observed. It was concluded that in terms of etiology upper lip cancer could be regarded as a separate entity and different from "true" lip cancer of the lower lip. The role of recurrent herpetic infections of the lips is also discussed.

Adult↗
PubMed1979

Risk factors in lip cancer: a questionnaire survey.

An analysis was made of potential risk factors of cancer of the lip in Finland. The series comprised 290 lip cancer patients, and the controls were 254 patients with squamous cell carcinoma of the skin of the head and neck, all reported to the Finnish Cancer Registry in 1972-1973. The results obtained in a questionnaire survey (response rate, 75%; 54% of the total series) indicated that the male lip cancer patients had engaged in outdoor work and smoking with significantly greater frequency than had the male controls. Together, these two risk factors posed a markedly increased risk (RR = 15.4). However, when the factors were analyzed separately, each excluding the effect of the other, no significant risk could be noted. The male lip cancer patients had recurrent herpetic infections with significantly greater frequency than did the male controls. No significant differences were apparent with respect to urban or rural residence. It is concluded that tobacco smoking and outdoor work probably act together to induce lip cancer. The mode of interaction between these factors and the etiologic role of herpesvirus are discussed.

Aged↗
PubMed1979

Second primary cancers in patients with carcinoma of the lip.

The occurrence of second primary cancers in patients with lip cancer was evaluated in order to test certain etiologic hypotheses. All cases of lip cancer reported to the Finnish Cancer Registry in 1953-74 (3303 men, 320 women) were followed up for a second (or third) primary cancer through the files of the Registry either to death or to 31 December 1974 (a total of 25 510 person-years). The expected numbers of cases were calculated on the basis of the incidence rates specific for sex, age, time and residence (urban or rural) in Finland. A higher than expected risk of cancer was found among both urban and rural male lip cancer patients; among women the observed number of new primary cancers did not differ from that expected. A significant excess risk among males was noted for cancers of the lung and larynx (rural patients) and for non-melanomatous skin cancer in locations other than the head and neck (urban patients). The association of cancers of the lip, lung and larynx found earlier on a geographic level supports the hypothesis that tobacco smoking is a common risk factor in these cancers. The differences in the relative risks between urban and rural patients, however, suggest that the risk factors in lip cancer in urban areas might be partially different from those prevalent in the rural population. The results do not support the hypothesis that sunlight is an important risk factor in lip cancer.

Adult↗
PubMed1979

Risk factors of lip cancer: a critical evaluation based on epidemiological comparisons.

A description is given of the occurrence of lip, skin, and intraoral cancers in Finland in the period 1953-1973 with the aim of testing certain etiologic hypotheses. In addition, data on lip cancer were correlated with those of some other types of cancer. Substantial differences with respect to various epidemiologic parameters were found between lip and skin cancers. However, there were similarities between lip cancer and cancers of the upper gastrointestinal canal and respiratory organs (especially lung cancer). Negative geographic correlation was found between the age-adjusted incidence rate of lip cancer and that of cancers of the colon and prostate. In addition, the correlation was highly negative for the median income per capita (p less than 0.001). It was concluded that, in terms of cancer etiology, lip cancer is more closely related to cancer of the oral cavity than to that of the skin. Moreover, some specific socioeconomic factors associated with a low standard of living must be considered as noteworthy risk factors of lip cancer.

Age Factors↗