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71.
Sini Nurmenniemi Teemu Sinikumpu Ilkka Alahuhta Sirpa Salo Meeri Sutinen Markku Santala Juha Risteli Pia Nyberg Tuula Salo 《The American journal of pathology》2009,175(3):1281-1291
Carcinoma cell invasion is traditionally studied in three-dimensional organotypic models composed of type I collagen and fibroblasts. However, carcinoma cell behavior is affected by the various cell types and the extracellular matrix (ECM) in the tumor microenvironment. In this study, a novel organotypic model based on human uterine leiomyoma tissue was established and characterized to create a more authentic environment for carcinoma cells. Human tongue squamous cell carcinoma cells (HSC-3) were cultured on top of either collagen or myoma. Organotypic sections were examined by immunohistochemistry and in situ hybridization. The maximal invasion depth of HSC-3 cells was markedly increased in myomas compared with collagen. In myomas, various cell types and ECM components were present, and the HSC-3 cells only expressed ECM molecules in the myoma model. Organotypic media were analyzed by radioimmunoassay, zymography, or Western blotting. During carcinoma cell invasion, matrix metalloprotease-9 production and collagen degradation were enhanced particularly in the myoma model. To evaluate the general applicability of the myoma model, several oral carcinoma, breast carcinoma, and melanoma cell lines were cultured on myomas and found to invade in highly distinct patterns. We conclude that myoma tissue mimics the native tumor microenvironment better than previous organotypic models and possibly enhances epithelial-to-mesenchymal transition. Thus, the myoma model provides a promising tool for analyzing the behavior of carcinoma cells.Tumor growth and invasion are not just determined by the malignant tumor cells, but instead various cell types and the extracellular matrix (ECM) of the tumor microenvironment affect the outcome.1 Particularly, fibroblasts have many prominent roles in the cancer progression. In fact, in many carcinomas, the majority of the stromal cells are fibroblasts that possess myofibroblastic characteristics and are called cancer-associated fibroblasts. They produce ECM molecules, proteases, growth factors, and chemokines that crucially affect the carcinoma cell behavior.2,3 In this context, the organotypic three-dimensional skin model developed by Fusenig et al4 replicates the in vivo situation more closely in vitro than the two-dimensional cell culture experiments. The model allows studying of carcinoma cell invasion in three-dimensional collagen gel embedded with fibroblasts. The degree of invasion can also be quantitatively analyzed.5,6 However, this kind of organotypic model remains somewhat artificial due to the lack of other cell types besides fibroblasts and ECM components that are present in vivo. In addition to the carcinoma cells and fibroblasts, endothelial and inflammatory cells, as well as several ECM molecules, are known to contribute to the tumor growth. The induction of angiogenesis, recruitment of inflammatory cells, and increased turnover of ECM components result in tumor progression.7,8 Therefore, we wished to determine whether real human tissue can be used in the organotypic method to provide a more natural stroma-like environment for studying carcinoma cell invasion. We used uterine leiomyoma tissue, which mainly consists of smooth muscle actin (SMA)-positive cells and collagens.9 The existence of various additional cell types and proteins in the myoma tissue was characterized, and the invasiveness of malignant human tongue squamous cell carcinoma cells (HSC-3) into this novel myoma organotypic culture was measured by different methods and compared with the traditional collagen organotypic model. To test the general applicability of the myoma model, the invasion patterns of various cell lines were examined in myoma and collagen organotypic cultures. 相似文献
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73.
Timo Aro Lasse Kanerva Ritva Häyrinen-Immonen Sylvi Silvennoinen-Kassinen Yrjö T. Konttinen Riitta Jolanki Tuula Estlander 《Contact dermatitis》1993,28(5):276-281
Allergic contact dermatitis caused by gold is rare, and only isolated cases have been reported. Patch Jesting with gold may cause a long-lasing reaction. The purpose of this study is to describe a well-studied case of gold allergy caused by denial gold crowns. A gold-sensitized patient and a non-sensitized control subject were examined using patch tests, immunohistochemistry. electron microscopy and blast transformation reactions. Sodium thiosulfate, auranofin and sodium thiomalate gave positive patch test reactions. Immunohistochemistry and electron microscopy were performed from biopsies taken from allergic patch lest reactions caused by gold sodium thiosulfate 1 day and 17 days after applying the patches, from normal skin and from a 17-day-old allergic patch test reaction caused by ammonium persulfate. Down-regulation had taken place by 17 days in the allergic ammonium persulfate reaction, but not in the 17-day allergic gold lest reaction. The patient reacted to all but one of the gold-induced blast transformation tests, sodium chloroaurate being non-inductive. The non-sensitized control subject did not exhibit any reactions. In conclusion, gold sodium thiosulfate, gold sodium thiomalate and auranofin can be used as patch test substances for gold allergy, though long-lasting allergic patch test reactions may develop. In vitro gold salt induced blast transformation is an alternative test for gold allergy. The slow down-regulation of the allergic patch test reactions needs to be studied further. 相似文献
74.
Unsaturated polyester (UP) cement caused allergic contact dermatitis in car repair work. The resin was a condensate of polyols and maleic anhydride with reactive solvent, auxiliary substances, and inorganic reinforcement substances. To identify the causative chemicals, the cement was tested on a sensitized patient. For analysis, samples of the resin were eluted with acetone and eluted with hexane to precipitate inorganic material and large polyester molecules. The eluate was evaporated. The remainder, dissolved in acetone, was separated into fractions on silica plates by thin layer chromatography (TLC). On the developed (hexane/chloroform, 15/85) plates, 20 bands were obtained under UV-light at 254 nm. Samples of the bands were scraped and used for patch testing. The scraping at a retention factor (Rf) of 0.24 caused a skin reaction. The bands at this retention were removed from six plates, combined, eluted with acetone and purified again by TLC. The purified fraction mixed in petrolatum in the dilution series was used for conclusive patch testing on the patient. An allergic reaction was induced at down to 0.003% wt/wt. According to MS and IR analyses, the isolated compound was diethyleneglycol maleate (DEGM, MW204). In addition to the resin part, the sanding dust also contained this monomer. 相似文献
75.
Alarmo EL Kuukasjärvi T Karhu R Kallioniemi A 《Breast cancer research and treatment》2007,103(2):239-246
Bone morphogenetic proteins (BMPs) regulate diverse cellular processes, such as proliferation, differentiation, and apoptosis.
The BMPs have been studied in several cancers, but thus far contradictory results have been obtained and, especially in breast
cancer, information on BMPs is still limited. We performed a systematic expression survey of BMPs and their receptors in breast
cancer. mRNA expression was studied of seven BMP ligands (BMP2-BMP8) and six receptors (ACVR1, BMPR1A, BMPR1B, BMPR2, ACVR2A, and ACVR2B) that specifically mediate BMP signals. Expression levels were determined in 22 breast cancer cell lines, 39 primary breast
tumors, normal human mammary epithelial cell line, and normal mammary gland using semiquantitative RT-PCR. The expression
frequencies and expression levels of different BMPs varied considerably in breast cancer with BMP4 and BMP7 being most frequently expressed and showing highest expression levels. The BMP specific receptors were more uniformly expressed
and indicated that breast cancer is fully capable of transmitting BMP signals. Expression frequencies and levels for both
the ligands and the receptors were in good concordance between the breast cancer cell lines and primary tumors. We can conclude
that breast cancers possess functional BMP signaling machinery on the cell surface with distinct differences in the expression
of various BMP ligands. Our survey focuses the attention particularly toward BMP4 and BMP7 and suggests their importance in breast cancer. Breast cancer cell lines and the data generated here serve as a good resource
for further studies on BMP function in breast cancer. 相似文献
76.
Tuula Wallsten Margareta Östman Rickard L. Sjöberg Lars Kjellin 《Nordic journal of psychiatry》2013,67(6):444-449
The introduction of a new Civil Commitment Act in Sweden in 1992 involved a shift of emphasis from medical to judicial authority. Little is known about general patient attitudes to compulsory care. The aim of the study was to study possible differences in attitudes, before and after the mental health law reform, among involuntarily and voluntarily admitted patients and their next-of-kins towards involuntary psychiatric admission. Samples of 84 committed and 84 voluntarily admitted patients in 1991 and 118 committed and 117 voluntarily admitted patients in 1997–99 were interviewed within 5 days from admission and at discharge, or after 3 weeks of care. Samples of 64 next-of-kins to the committed patients and 69 next-of-kins to the voluntarily admitted patients in 1991, and 73 and 89 next-of-kins, respectively, in 1997–99 were interviewed approximately 1 month after the admission. Few changes in attitudes were found between the two study occasions. A majority of all patients stated that it should be possible to compulsorily admit patients, and a great majority of the patients and the next-of kins stated that decisions regarding compulsory admission should be taken by doctors. Most patients and next-of-kins regarded decisions about involuntary psychiatric care mainly as a medical matter. Strong support for coercion in order to protect the patient and others was found among next-of-kins. The law reform was not reflected in attitudinal differences. 相似文献
77.
The purpose of this research was to determine possible differences in the self-concept of chronically ill and healthy adolescents. A group of adolescents with diabetes mellitus type-I (DM) and a group with rheumatoid arthritis (RA) were chosen for the study, together with a control group without any chronic illness. The groups were matched for gender, age (DM 17.8, RA 17.9, control group 17.6 years) and social class. The Offer Self-Image Questionnaire (OSIQ) was used to estimate differences between the groups of 23 DM adolescents, 25 RA adolescents and 26 control group adolescents. The scores are reversed; thus the higher the score, the better the self-image. The results indicate that Body Image, and Vocational and Educational Goals were lower in the groups of chronically ill adolescents than in the control group; however, no statistically significant differences were found between the groups on the OSIQ scales. The self-image of adolescents with DM with good metabolic control and moderate and long-lasting RA is relatively well developed. 相似文献
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79.