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A Lindgren

Publications and source records attributed to A Lindgren.

At least 163 records · Page 9Linked to original sources
PubMed1989

Test-retest variability in glaucomatous visual fields.

We measured test-retest variations in computerized visual fields from glaucomatous eyes. Fifty-one patients were tested four times within a four-week period; the severity of disease varied from incipient to advanced. We determined the dependence of threshold variability on defect depth and test point location. In areas of the visual field initially found to have moderate loss of sensitivity, variation in follow-up measurements ranged from normal sensitivity to absolute defect, with little dependence on distance from fixation. Conversely, large changes were considerably more unusual in locations initially showing normal or near-normal sensitivities, and variability was lowest in the most central portion of the field. Our findings suggest that differentiation between true progression and random variation will be facilitated if these factors are taken into account, as well as if comparisons are based on more than two tests. The complex nature of interest variation in glaucoma makes it natural to approach this problem with the help of computer-assisted analyses.

Adult↗
PubMed1989

Risk of endometrial cancer after treatment with oestrogens alone or in conjunction with progestogens: results of a prospective study.

OBJECTIVE: To determine the relative risk of developing endometrial neoplasia after treatment with oestrogens alone or in conjunction with progestogens. DESIGN: Prospective cohort follow up study, average observation period 5.7 years for each patient. To have a 90% chance of detecting a relative risk of 2.0 with 95% significance the study required 78,000 person years of observation. SETTING: Community based cohort. PATIENTS: Women aged over 35 who were prescribed non-contraceptive oestrogens in the Uppsala health care region during April 1977 to March 1980 were identified from pharmacy records. Of all prescriptions issued, 95% were identified. Patients from the cohort who developed endometrial neoplasia were identified from the cancer registry of the Uppsala health care region. Compliance, sociodemographic data, and lifetime exposures to oestrogen and cyclically added progestogen were assessed by questionnaire in a sample of the cohort. The final cohort consisted of 23,244 patients (133,373 person years). The prevalence of university education, oophorectomy, and hysterectomy was higher in the cohort than the general population; no other confounding factors were identified. MEASUREMENTS: The total number of person years was divided into exposure groups by inference from the data from the questionnaire. Compensation was made for the excess of hysterectomies. Specimens from all cases of endometrial neoplasia in the cohort and 90% of cases in the general population were studied blind histopathologically. Characteristics of treatment of all women who had endometrial neoplasia were assessed by questionnaire. Relative risks and 95% confidence intervals were calculated. RESULTS: Seventy four cases of carcinoma and 33 cases of premalignant lesions occurred in the cohort. The relative risk of endometrial carcinoma was 1.8 (95% confidence interval 1.1 to 3.2) after exposure to any oestrogen compound without progestogen for more than six years; 2.2 (1.2 to 4.4) after more than three years' exposure to conjugated oestrogens without progestogen; and 2.7 (1.4 to 5.1) after more than three years' exposure to oestradiol compounds without progestogen. When carcinoma and premalignant lesions were considered together the results were similar but the relative risk was higher. Risk of carcinoma did not increase when progestogens were cyclically added to oestrogens for the entire treatment period (relative risk 0.9 (0.4 to 2.0]. CONCLUSIONS: Use of oestrogens without progestogens is associated with a twofold to threefold increase in risk of endometrial neoplasia. Use of progestogens either removes this increased risk or delays its onset. A further follow up of the cohort is essential to analyse the risks with greater statistical power.

Adult↗
PubMed1989

The accuracy of cytology in diagnosis and DNA analysis of canine mammary tumours.

Fine-needle aspirates from 84 spontaneous canine mammary tumours were used to assess the accuracy of this method in flow cytometric DNA analysis and cytological diagnosis. Defined samples from different tumour parts were analysed for histological diagnosis and DNA ploidy as a control. The DNA ploidy in cytology specimens and those obtained from the defined tumour samples, when testing for independence, was highly significant (P = 0.0001). The total accuracy of cytology was 79 per cent, with a sensitivity of 65 per cent and a specificity of 94 per cent. The results show the possibility of combining cytology and DNA analysis of fine-needle aspirates from canine mammary tumours. The method is suitable for preoperative diagnosis of canine mammary tumours as well as for measuring DNA ploidy, which makes it useful if DNA ploidy turns out to be of diagnostic and prognostic value in these tumours.

Animals↗
PubMed1989

Expression of placental alkaline phosphatase in epithelial ovarian tumours.

The expression of placental alkaline phosphatase in 116 ovarian epithelial tumours was examined in formalin-fixed tissues used for routine histopathologic examination. In the total material, 51% of the tumours displayed positive immunoreactivity, as described by the monoclonal anti-placental alkaline phosphatase antibody C2, with similar incidence (46-67%) in the four major groups of the adenocarcinomas, i.e., serous, mucinous, endometrioid and mesonephric tumours. By use of a histochemical staining index the mucinous and mesonephric tumours demonstrated a more intense staining (2.1 and 2.6) compared to the serous and endometrioid tumours (0.9 and 1.5). The relevance of the findings is discussed in relation to the use of monoclonal antibody technologies for radioimmunolocalization and radioimmunotherapy.

Alkaline Phosphatase↗
PubMed1989

The expression of intermediate filaments in canine mammary glands and their tumors.

Monoclonal antibodies specific for different types of intermediate filaments (cytokeratin, vimentin, desmin and neurofilaments) were used to study the histogenesis of canine mammary glands and 57 canine mammary tumors by immunocytochemistry. The intra- and interlobular duct epithelium, acinar, and intralobular myoepithelial cells stained positively for cytokeratin. Peripheral ductal and acinar cells, as well as interstitial cells, stained positively for vimentin. A similar staining pattern was seen in adenomas, complex adenomas, benign mixed tumors, ductular carcinomas, and one myoepithelioma-like tumor. Additionally, cytokeratin positive cells were scattered interstitially in one single adenoma, most complex adenomas, some benign mixed tumors, complex carcinomas, and in the malignant mixed tumors. All stromal cells stained positively for vimentin. The fibrosarcomas were positive only for vimentin, while the following expressed both desmin and cytokeratin: epithelial-like cells in one adenoma, three complex adenomas, the myoepithelioma-like tumor, the single comedo carcinoma, two complex carcinomas, the single lobular carcinoma, one malignant mixed tumor, and three osteosarcomas. Epithelial-like cells in one adenoma, six complex adenomas, two benign mixed tumors, two complex carcinomas, the lobular carcinoma, and the malignant schwannoma stained for neurofilaments. Three tumors, one adenoma, one complex adenoma, and the lobular carcinoma expressed both desmin and neurofilaments in addition to cytokeratin and vimentin. The results show the expression of different types of intermediate filaments and indicate that there might be a stem cell origin in most of the canine mammary tumors.

Adenoma↗
PubMed1988

Prognosis in bilateral breast cancer. Effects of time interval between first and second primary tumours.

Survival rates for 67 women with bilateral breast cancer were compared to those for 1282 women with unilateral disease in a follow-up of 1349 women participating in a population-based study. Relative survival at 8 years of follow-up was 69% for women with unilateral disease as compared to 53% for women with bilateral cancer. When possible confounding histopathological differences--data about which were prospectively collected--and age were adjusted for in a multivariate analysis, the relative hazard rate was significantly higher for women with bilateral versus unilateral breast cancer (P = 0.006). The impact of interval time between the two primaries was analysed and a roughly two-fold higher hazard rate was seen for synchronous cancers with regularly falling risk for increasing interval times. This trend was however not statistically significant. The results indicate that the two tumours contribute independently to the patient's excess risk of dying and thus occur as two seemingly biologically unrelated events with respect to the tumour-host relationship and metastatic behaviour.

Aged↗
PubMed1988

DNA patterns and aggressive histopathologic features in 159 patients with cervical carcinoma.

In 159 patients with invasive squamous cell carcinoma of the uterine cervix, flow cytometric DNA patterns were related to eight histopathologic parameters according to a malignancy grading system, in which four of the parameters concern the tumor cell population and four concern the tumor-host relation. Each parameter was graded from 1 to 3 points. Flow cytometrically aneuploid values, contrasted to peridiploid ones, were more often found in specimens with immature, irregular nuclei, as well as in specimens with diffuse growth (p less than 0.05), obvious vascular invasion (p less than 0.05) or slight or no plasmolymphocytic response (p less than 0.05). For each histopathologic parameter, higher mean S-phase rates were found for the aggressive 3-point tumors than for the 1-point tumors. Tumors with total scores of 11-17 points were more often peridiploid than tumors with 18-22 points.

Adult↗
PubMed1988

Prognostic significance of the Ackerman classification and other histopathological characteristics in breast cancer. An analysis of 1,349 consecutive cases with complete follow-up over seven years.

Survival rates during a follow-up period of more than seven years were analyzed in 1,349 women with breast cancer in relation to the histo-pathological classification of female breast cancer proposed by Ackerman and to other commonly used histo-pathological criteria, including the axillary node status. The information was collected prospectively during a case-control study. Major emphasis was placed on multivariate evaluation. In analyses based on the histo-pathological findings in the mastectomy specimen alone, the Ackerman grouping was found to be of prognostic value, but apart from nuclear polymorphism the other recorded characteristics (histo-pathological type, histological grading, lymphocyte infiltration, and sinus histiocytosis) did not give any prognostic information. When the axillary node status was included in the multivariate models, the presence of axillary metastases correlated well with the prognosis and the Ackerman classification provided no significant additional information. The results indicate that in cases where the histopathological axillary status is known, little additional prognostic information can be gained from traditional histo-pathological evaluation over and above this status. However, the Ackerman classification and the degree of nuclear polymorphism separate distinct prognostic groups with the same degree of difference in observed survival rates as one discriminated by the axillary node status.

Breast Neoplasms↗
PubMed1988

Comparison of histology and clinical variables to DNA ploidy in canine mammary tumors.

Flow cytometric DNA analysis was done on 132 canine mammary tumors from 99 dogs to evaluate the relation to histology and to clinical staging. Seventy-one tumors (54%) were histologically malignant; 38 (54%) of these were aneuploid and 33 (46%) were diploid. Fifty-two (39%) tumors were histologically benign, of which 45 (87%) were diploid and seven (13%) aneuploid. There were nine dysplastic mammae (7%); two were aneuploid and the rest diploid. DNA indices varied from 0.72 to 2.35. Of 58 mammary carcinomas, 25 (43%) were diploid and 33 (57%) were aneuploid (of the latter, 16 showed hypodiploidy and 17 hyperdiploidy with a predominance between DNA index 1.10 and 1.50). Three tumors (two carcinomas and one malignant mixed tumor) were multiploid with two aneuploid cell populations. The histological type varied within eight tumors, and in four of these the DNA index also varied. DNA indices varied within three tumors with uniform morphology. No correlation was found between DNA index and age of the dogs, nor between DNA index and tumor size. No significant differences were found between DNA index and histology, tumor growth pattern, or tumor location. Benign tumors were smaller than carcinomas, which were smaller than malignant mesenchymal tumors. Tumors growing adherent to the skin were larger than those not adherent to the skin. The regional lymph nodes were examined in 33 cases. No significant difference between the mean DNA index and presence of lymph node metastasis was found. These results show the possibility of using flow cytometry for DNA analysis in canine mammary tumors.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Involvement of transferrin in the reduction of iron by the transplasma membrane electron transport system.

Nonpermeable electron acceptors can be reduced by a transplasma membrane electron transport system in suspensions of intact cells. Here we report that diferric transferrin is reduced by HeLa S3 cells. The reduction is recorded spectrophotometrically as the formation of the ferrous complex of bathophenanthroline disulfonate. Ferric ammonium citrate can also be used as an electron acceptor and the presence of low concentrations of diferric transferrin greatly stimulates the reduction of trivalent iron under these conditions. Likewise very low concentrations of ferricyanide, which does not give rise to a ferrous bathophenanthroline disulfonate complex formation, have a strong stimulatory effect on the complex formation when ferric ammonium citrate is the source of ferric iron. Apotransferrin is a potent inhibitor of the reaction. The inhibition occurs at the concentration necessary for complete occupancy of the transferrin receptors. The inhibition can be demonstrated also when high concentrations of ferricyanide are used as electron acceptor. The possible mechanism behind the reported phenomena is discussed, and it is concluded that the transplasma membrane electron transport system can be involved in the process of cellular iron uptake.

Apoproteins↗
PubMed1987

Endometrial morphology after 6 months of continuous treatment with a new gonadotropin-releasing hormone superagonist for contraception.

Light and electron microscopic studies were performed on endometrial curettage specimens from 27 women after 6 months of contraceptive treatment with continuous intranasal gonadotropin hormone-releasing hormone (GnRH) superagonist. The GnRH superagonist nafarelin acetate (D-Nal[2]6-GnRH) was used in single daily doses of 125 or 250 micrograms. Ovulation was inhibited during all but one of the 159 treatment months. No pregnancies occurred. In 6 women with fairly regular bleedings, the endometrium displayed weak to normal proliferation. Twenty women developed oligomenorrhea or amenorrhea, 16 of them had inactive endometrium, 1 had weakly proliferative endometrium, and 3 endometrial biopsies were too sparse for adequate evaluation. One woman reported repeated episodes of heavy uterine bleedings. The endometrial biopsy from this woman showed weak proliferation. No signs of endometrial hyperplasia were observed. Generally, the electron microscopy showed signs of low metabolic activity and weak protein synthesis. Thus, long-term continuous treatment with nafarelin acetate for inhibition of ovulation does not appear to have untoward effects on the endometrium.

Administration, Intranasal↗
PubMed1987

Neuron-specific enolase expression and neuroendocrine differentiation in carcinomas of the breast.

The concentration of neuron-specific enolase (NSE, gamma-subunit of enolase) in tumor extracts of 25 nonargyrophilic and seven argyrophilic carcinomas of the female breast was measured by radioimmunoassay. The mean concentration of NSE in nonargyrophilic carcinomas was 89 ng/mg of protein, (range, 9 to 281 ng/mg), and the mean concentration of NSE in argyrophilic carcinomas was 153 ng/mg of protein (range, 4 to 420 ng/mg). All carcinomas, irrespective of the silver reaction, could be grouped in regular histopathologic terms. Neuron-specific enolase immunoreactivity in sections of the corresponding fixed tumors occurred in both silver-stained and unreactive tumors, although the reaction was more prominent in the argyrophilic tumors. The results indicate that NSE in considerable amounts may be present in both argyrophilic and nonargyrophilic carcinomas of the breast, although higher concentrations are found most often in the former tumor type.

Aged↗
PubMed1986

Reliability of endometrial cancer diagnoses in a Swedish Cancer Registry--with special reference to classification bias related to exogenous estrogens.

In this study, various qualitative aspects of endometrial cancer diagnoses were critically evaluated regarding cases included in the Swedish Cancer Registry from the Uppsala Health Care Region. By comparing the number of such cases in the registry with cases reported directly from the departments of pathology and of gynecological oncology in the same region, it was found that approximately 5% of all incident cases had not been notified to the registry. An independent histopathological review of the original specimens showed that almost 9% of the cases did not represent an endometrial neoplastic lesion, the majority of these being reclassified as uterine sarcoma. The review also revealed the problem of a diagnostic bias that might arise in connection with estrogen exposure, in that a significantly higher proportion of the cases observed in a cohort of women who had received estrogen prescriptions were reclassified as a premalignant endometrial lesion than of the cases from the background population without estrogen exposure (33% versus 10%). Additional independent reviews of cases showing discordant diagnoses in the primary review indicated variability in diagnostic criteria among pathologists. It is concluded that when cancer registry data are employed in epidemiological studies of endometrial cancer, the use of additional sources of case recruitment is desirable in order to obtain a complete material; also that an independent histopathological review is necessary to standardize diagnostic criteria and thereby to avoid a classification bias.

Estrogens↗
PubMed1986

The risk of endometrial neoplasia and treatment with estrogens and estrogen-progestogen combinations. First results of a cohort study after one to four completed years of observation.

This prescription-based cohort investigation was undertaken in order to study whether climacteric estrogen treatment of women in a Swedish population might be associated with an increased risk of endometrial cancer, and whether added progestogens can afford any protection from developing estrogen-related endometrial neoplasia. Some 23 000 women who had been prescribed estrogens were followed up regarding the outcome of neoplastic lesions of the endometrium. The results are based on an observation period of one to four completed years, corresponding to 89 000 person-years. Among those cohort members exposed to estrogens alone, regardless of the duration, the relative risk of endometrial cancer was 1.3 (95% confidence interval 0.9 to 1.7). The inclusion of premalignant endometrial changes resulted in a significantly increased relative risk of 1.6 (1.2-2.1). The relative risk estimates in association with estrogen-progestogen combinations were 0.6 (0.2-1.4) for endometrial cancer and 0.8 (0.4-1.5) when including premalignant lesions. These data indicated a possible protective effect of progestogens against the development of endometrial neoplasia. It was concluded that estrogens were - within an observation period of 4 years - associated with an increased risk of premalignant endometrial lesions.

Adult↗
PubMed1986

Climacteric symptoms and estrogen replacement therapy in women with endometrial carcinoma.

A case-control study was undertaken to investigate the influence of exogenous estrogens and climacteric symptoms on the risk of developing endometrial carcinoma. The study comprised 254 women with newly diagnosed endometrial carcinoma, resident in a defined geographical area, and 254 age-matched population controls. Treatment with estrogens for 4 years or longer was significantly more common among patients than among controls (odds ratio = 4.5; 95% confidence limit (CL) = 1.2-17.3). A history of climacteric symptoms was reported by significantly fewer patients than controls (odds ratio = 0.5; 95% CL = 0.3-0.7) and this difference was shown to be independent of weight. The decrease in risk associated with climacteric symptoms was limited to women younger than 70 years.

Adult↗
PubMed1986

[Not Available].

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Denmark↗
PubMed1986

Quantitation of estrogen receptor in seventy-five specimens of breast cancer: comparison between an immunoassay (Abbott ER-EIA monoclonal) and a [3H]estradiol binding assay based on isoelectric focusing in polyacrylamide gel.

Quantitation of estrogen receptor has been performed in cytosol prepared from 75 specimens of breast cancer tissue from patients who had not received hormonal therapy. The study was performed in order to compare an immunoassay (Abbott Laboratories, North Chicago, IL) with our currently used method for estrogen receptor analysis based on isoelectric focusing of [3H]estradiol-receptor complex in polyacrylamide gels. Using linear regression analysis, a regression coefficient (slope) of 1.30 and a correlation coefficient of 0.75 were calculated. The differences in results between the two methods are probably partly explained by the fact that the ligand-based method only measures unoccupied receptor, whereas the immunoassay detects the total amount of receptor, resulting in generally slightly higher concentrations with the latter method. However, in five of 75 specimens the ligand-based method gave a considerably higher concentration of estrogen receptor. This was most probably explained by partial proteolysis resulting in the formation of receptor fragment(s), which was undetectable with the immunoassay but detectable with the ligand-based method. These observations underline the importance of careful handling of specimens during the whole immunoassay procedure.

Acrylic Resins↗