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Biomedical subjects

L Christensen

Publications and source records attributed to L Christensen.

At least 127 records · Page 7Linked to original sources
PubMed1990

Histologic changes and silicone concentrations in human breast tissue surrounding silicone breast prostheses.

Using a previously developed method for quantitative measurements of silicone concentrations in breast tissue, material from 86 biopsies from 67 breasts in 55 patients who had silicone implants was examined. In the 49 breast with unruptured prostheses, there was a positive relation between the concentrations and inflammatory reactions, the only exception being the amount of plasma cells, which showed a negative relation. It is concluded that silicone prostheses provoke an inflammatory response not only because they act as foreign bodies, but also because of silicone seepage through intact membranes.

Breast↗
PubMed1990

Fibronectin: a discrimination marker between small invasive carcinomas and benign proliferative lesions of the breast.

The connective tissue glycoprotein, fibronectin (FN) is known to be increased in the stromal desmoplastic response associated with invasive breast carcinoma (IBC). In a previous study of 77 IBCs we found that all tumours, irrespective of desmoplasia, displayed an intense stromal immunoreactivity for FN, although those with a high metastatic potential tended to lack this in foci along their infiltrating border (Christensen et al. 1988). In order to test the diagnostic value of this observation, FN immunoreactivity was estimated semiquantitatively in 131 small primary IBCs, 23 in situ carcinomas, 20 borderline lesions, 142 benign proliferative breast lesions and 35 samples of normal breast tissue. All IBCs, including those without apparent desmoplasia, were accompanied by an intense stromal staining for FN forming a diffuse or pericellular pattern around the tumour cells (FN positive reaction). This was not seen in the benign lesions (FN negative reaction) with the exception of an FN positive, linear staining around some cysts and ectatic ducts and a diffuse staining of the connective tissue core of some intraductal papillomas. Intraductal carcinomas, multiple papillomas and radial scars could display a substantial staining for FN, sometimes enclosing small islands or tubules of epithelial cells. However, the fact that all IBCs of this study produced an overall reliable and consistent FN positive stromal reaction, which was only interrupted in minute foci along the infiltrating border in a few of the largest tumours (11/131), makes immunohistochemical staining for FN an excellent adjunct to morphology in tracing small, primary IBCs.

Biomarkers, Tumor↗
PubMed1990

Identification of a highly mobilizable subset of human neutrophil intracellular vesicles that contains tetranectin and latent alkaline phosphatase.

Tetranectin, a protein recently identified in a wide variety of human secretory cells (Christensen, L., and I. Clemmensen. 1989. Histochemistry. 92:29-35) was found to colocalize with latent alkaline phosphatase activity in fractions well separated from azurophil granules, specific granules, gelatinase-containing granules, and plasma membranes when postnuclear supernatants of nitrogen-cavitated neutrophils were fractionated on discontinuous Percoll density gradients. Stimulation of intact neutrophils with nanomolar concentrations of FMLP, leukotriene B4, 10-100 U/ml of tumor necrosis factor, and granulocyte-macrophage colony-stimulating factor resulted in parallel release of tetranectin and translocation of alkaline phosphatase to the plasma membrane. Furthermore, intracellular pools of tetranectin and latent alkaline phosphatase were completely released from neutrophils under conditions that barely induced release of specific granules containing B12-binding protein. These findings indicate that tetranectin and latent alkaline phosphatase define an easily mobilizable population of cytoplasmic storage organelles in human neutrophils which are functionally distinguishable from azurophil, specific, and gelatinase-containing granules. These organelles may play an important role as stores of membrane proteins that are mobilized to the cell surface during stimulation by inflammatory mediators.

Alkaline Phosphatase↗
PubMed1990

Expectancy effects in caffeine research.

The impact of expectancy on the experience of caffeine-related symptoms was investigated by randomly assigning subjects to an expectancy or nonexpectancy instructional condition. Subjects were administered the State-Trait Anxiety Inventory and a Symptom Questionnaire prior to and 45 minutes after receiving their designated instructional set and ingesting a cellulose-filled gelatin capsule which ostensibly was filled with caffeine. Results revealed that a significant expectancy effect existed on five Symptom Questionnaire items.

Adult↗
PubMed1990

Erasmus.

The member countries of the EEC have decided to increase the mobility of students and teachers via the ERASMUS project. The purposes of ERASMUS are: to improve the number of inter-university exchanges; to increase the number of students and the mobility of teachers; to contribute to common developments of study programmes; to support intensive programmes for teachers and students among the countries of the EEC.

European Union↗
PubMed1989

Tetranectin immunoreactivity in normal human tissues. An immunohistochemical study of exocrine epithelia and mesenchyme.

A recently discovered human plasma protein, tetranectin (TN), which has previously been demonstrated immunohistochemically within various endocrine tissues, was in this study identified in an additional number of epithelial and mesenchymal cells by two polyclonal antibodies and one monoclonal using the conventional immunoperoxidase staining technique and a modification of the CLONO-GLAD procedure. TN was found in endothelial and epithelial tissues, particularly in cells with a high turn-over or storage function such as gastric parietal and zymogenic cells, absorptive surface epithelium of the small intestine, ducts of exocrine glands and pseudostratified respiratory epithelium. Also mesenchymal cells produced a TN positive staining reaction, which was most conspicuous in mast cells, but also present in some lymphocytes, plasma cells, macrophages, granulocytes, striated and smooth muscle cells and fibroblasts. SDS-PAGE and Western blotting analysis of cultured human embryonal fibroblasts (WI-38) showed that the cells besides TN contain another protein with a molecular weight of 82,000. As this protein, however, reacted with our affinity purified antibodies it probably represents a precursor of TN or a protein with a molecular weight of approximately 60,000, which is covalently linked to TN. This and the fact that TN shows amino acid sequence homologies to the carboxyterminal part of the asialo-glycoprotein receptor and a cartilage proteoglycan core protein as well a binding affinity to plasminogen points to TN as being part of a larger molecule, which possibly has been cleaved by proteolysis at the cellular site and then passed into the blood, where it polymerizes into a tetramer.

Antibodies↗
PubMed1989

Single pulse pressure wave analysis by fast Fourier transformation.

Pressure recordings from 16 patients with normal pressure by hydrocephalus were analysed during controlled intracranial hypertension. Single pulse pressure wave (PPW) analyses were performed on a computer system with programs for automatic computation of mean intracranial pressure (MICP), pulse amplitude (PA), rise time coefficients (RT) and fast Fourier transformation (FFT). We found good correlation between the first harmony, MICP and PA, and between the fifth harmony and RT. The PPW is mainly composed of low-frequency components, but with increasing RT more high-frequency components are present. RT changes as compliance of the brain changes. Therefore the high-frequency components of the FFT may predict changes in the cerebral compliance, although there was no correlation between any of the harmonies and the pressure volume index (PVI). In this investigation PVI was found difficult to perform and evaluate.

Aged↗
PubMed1988

Stromal fibronectin staining pattern and metastasizing ability of human breast carcinoma.

The peripheral stromal fibronectin (FN) staining patterns of invasive breast carcinomas (IBC) from 77 women were compared to the aggressivity of the tumors, which in each case had been determined through a complete clinical follow-up and autopsy investigation. Polyclonal, monospecific rabbit antibody to human FN was applied on formalin-fixed, paraffin-embedded tissue sections using the peroxidase-antiperoxidase staining technique. An FN-positive staining reaction was defined as a constant, diffuse, or pericellular demarcation of FN-positive fibers surrounding tumor cells at the invasive border. In lack of such a staining pattern, FN-negative staining was recorded. The FN-positive staining reaction was significantly associated with a low metastatic potential and appeared in a multivarians analysis to be an excellent prognostic factor, which surpassed other known parameters, such as clinical stage, histological type or grade, and lymph node status. 27 out of 31 women, who died without evidence of metastatic spread, had FN-positive IBC (87%) in contrast to women with metastatic disease, where only 15 out of 46 had FN-positive tumors (33%). An extensive histopathological examination of the contralateral breast revealed in this latter group a high rate of second primaries (22/46), which might have been responsible for the metastatic spread. If these women with bilateral IBC were excluded, only three metastasizing tumors with a FN-positive staining pattern remained, suggesting that the prognostic value of the FN-staining pattern along the invasive border of IBC might be even higher than anticipated from this study.

Analysis of Variance↗
PubMed1988

Axillary lymph node morphology in women with in situ breast carcinoma. An autopsy study.

Axillary lymph nodes in 184 female autopsy cases were studied using morphological criteria. Special attention was paid to the morphology in 34 women with in situ breast carcinoma (in situ BC) compared to the remaining women without malignant breast lesions, who served as controls. Sinus histiocytosis (SH) and diffuse cortical hyperplasia (DCH) were significantly more frequent among women with in situ BC compared to controls. No significant association was found between unilateral in situ BC and these lymph node patterns on the contralateral side. Germinal center and follicular hyperplasia (GCH/FH), lymphocyte depletion (LD), fibrosis, hyalinization, calcifications and lipomatosis were not associated with in situ BC. The results indicate that in situ BC provokes reactive morphological changes of the regional axillary lymph nodes similar to the changes associated with a good prognosis in women with invasive breast cancer (IBC).

Adult↗
PubMed1988

Glucocorticoid receptors in glioblastoma multiforme: a new approach to antineoplastic glucocorticoid therapy.

Glucocorticoid receptors were measured in tissue samples from 12 patients with glioblastoma multiforme. The receptor was found in all patients. The concentration of glucocorticoid receptor was found to be high in the periphery of the tumour, low in the surrounding brain tissue and low in the central part of the tumour in 6 of the patients. The possible role of the glucocorticoid receptor distribution in relation to growth regulation is discussed. A decreasing receptor concentration found at reoperation in two patients indicates a possible antineoplastic effect of high dose methylprednisolone pulse therapy on glucocorticoid receptor positive glioblastomas.

Adult↗
PubMed1988

Immunohistochemical study of intimal protein deposits in the aging vascular wall of normo- and hypertensive patients.

In an attempt to obtain immunohistochemical data of use for evaluating the severity and extent of intimal thickening (IT) in normo- and hypertensive patients small-sized arteries were analyzed by the immunoperoxidase staining technique for intimal deposition of albumin, fibrinogen, IgG, IgM and beta-lipoprotein. The material included surgical biopsies from 143 temporal arteries and matched autopsy samples of temporal- and interlobar renal arteries from 33 patients. The intimal protein deposits were found to reflect the presence of IT but not the state of hypertension. comparisons between the matched temporal and renal arteries showed rank correlation regarding IT as well as deposition of fibrinogen, IgG and beta-lipoprotein. However, fibrinogen was the only protein, which also showed congruous mean values for the two different arterial types. We therefore conclude that out of the 5 proteins examined in this study, fibrinogen appears to be the most reliable marker of IT in small-sized arteries.

Adult↗
PubMed1988

Silicon in human breast tissue surrounding silicone gel prostheses. A scanning electron microscopy and energy dispersive X-ray investigation of normal, fibrocystic and peri-prosthetic breast tissue.

Implanted silicone breast prostheses leak silicone gel through the intact membrane. In order to determine the exact location and to achieve a semiquantitative estimation of the amount of silicone in the surrounding tissue, a method involving scanning electron microscopy (SEM) and energy dispersive analysis of X-rays (EDAX) was used. By this method we were able to demonstrate the presence of the element silicon (Si) (main component of silicone, a polymer with a general formula e.g. (CH3[Si(CH3)2O]n Si(CH3)3 along the inner border of vacuoles corresponding to the light microscopic localization of droplets and in macrophages. The tissue adjacent to the prostheses had a higher silicon content than the control tissue.

Breast↗
PubMed1988

Sarcomas of the breast: a clinico-pathological study of 67 patients with long term follow-up.

A national Danish series of 68 breast sarcomas from 66 women and one man (age 17-86 years) was investigated. Tumour sections from 22 stromal sarcomas (SS), 24 phyllodes tumors of malignant type (MCSP), seven phyllodes tumors of borderline type (BLCSP), four malignant fibrous histocytomas (MFH), eight liposarcomas, two angiosarcomas and one leiomyosarcoma were reviewed retrospectively, and all patients were traced with a minimum follow-up of 15 years. Tumor contours appeared to be the best prognostic factor in predicting the risk of metastatic spread. Stromal overgrowth of MCSP was considered less utilizable due to difficulties in distinguishing between MCSP with marked stromal overgrowth and SS, which we consider as a variety of MCSP and which only showed slightly increased death rates compared to MCSP (45% versus 38%). Both angiosarcomas and the leiomyosarcoma proved lethal, and the other sarcoma subtypes had a death frequency of about 50%, with the exception of BLCSP, neither of which proved lethal. All patients, who died from metastases, were dead within 5 years irrespective of treatment. No positive lymph nodes were identified at the time of primary treatment, supporting the findings of previous investigators. We therefore advocate simple mastectomy or local excision with a wide margin as sufficient treatment of breast sarcomas. The indications for adjuvant therapy is as yet unclarified.

Adolescent↗
PubMed1987

Radial scars in women with breast cancer.

In 84 consecutive autopsies of women with a clinical diagnosis of invasive breast cancer, radial scars were found in the contralateral breast in 35 cases (42%) by an extensive histopathologic method. Four women had radial scars on the ipsilateral side in the breast tissue available from the primary surgical procedure or at autopsy. One woman had an invasive breast cancer with morphologic features compatible with but not diagnostic of transition from a radial scar. Of the six radial scars with carcinoma in situ occurring in three women, three were of ductal and three of lobular type. In the remaining cases only radial scars with a benign appearance were found except for two with atypical hyperplasia. The frequency of radial scars was significantly higher in women with fibrocystic disease (55%) compared to women without (24%). Contralateral primary invasive and in situ breast cancer occurred in 68%. No difference in the frequency of radial scars in women with and without breast cancer was found and radial scars were not associated with any specific type of breast cancer. Our findings do not indicate a higher malignant potential of radial scars than of fibrocystic disease. It is suggested that only radial scars containing high-risk epithelial changes such as atypical hyperplasia and carcinoma in situ are associated with an increased risk of subsequent breast cancer development.

Adult↗
PubMed1987

Immunohistochemical localization of a novel, human plasma protein, tetranectin, in human endocrine tissues.

A monospecific antibody to a plasminogen kringle 4-binding tetramer protein of human blood, tetranectin, was applied to various human endocrine tissues employing the peroxidase-antiperoxidase staining technique. Endocrine cells with a known protein or glycoprotein hormonal production such as chromophils (pituitary), follicular and parafollicular cells (thyroid), chief cells (parathyroid), hepatocytes (liver), islet cells (pancreas) and ganglion cells of the adrenal medulla displayed a convincing, positive staining reaction for tetranectin, which varied from cell to cell within the different tissues. The liver showed a distinct and universal reaction within almost all hepatocytes, thus raising suspicion of producing the bulk of tetranectin to the blood. Tetranectin has recently been characterized as a lectin-like protein with amino acid sequence homology to the core protein of a rat chondrosarcoma proteoglycan. Proteoglycans have been demonstrated in secretory granules of rat pituitary and pancreatic islet cells, where they probably serve as modulators in hormonal production. The granular, cytoplasmic immunohistochemical localization of tetranectin demonstrated in this study combined with the fact that tetranectin is known to attach to plasminogen and promote plasminogen activation catalysed by tissue plasminogen activator suggests that this protein might have a dual function, serving both as a regulator in the secretion of certain hormones and as a participant in the regulation of the limited proteolysis, which is considered important for the activation of prohormones.

Blood Proteins↗