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851.
852.
Moser C Jensen PO Kobayashi O Hougen HP Song Z Rygaard J Kharazmi A H by N 《Clinical and experimental immunology》2002,127(2):206-213
Repeated challenge with antigen is involved in the pathogenesis of a variety of pulmonary diseases. Patients with cystic fibrosis (CF) experience recurrent pulmonary colonization with Pseudomonas aeruginosa before establishment of chronic lung infection. To mimic recurrent lung infections in CF patients, the lungs of susceptible BALB/c mice were re-infected with P. aeruginosa 14 days after the initial infection. Singly-infected BALB/c mice, as well as non-infected mice, were used as controls. Decreased mortality and milder lung inflammation in re-infected BALB/c mice, as well as a tendency for improved clearance of bacteria, was observed when compared with singly-infected mice. The improved outcome in re-infected mice correlated with changes in CD4 cell numbers. Surface expression of LFA-1 on pulmonary CD4 cells was increased in re-infected compared with singly-infected mice. Moreover, resistance to re-infection was paralleled by a shift towards a Th1-dominated response and increased IL-12 production. No significant increase in serum IgG was observed in the re-infected mice. In conclusion, these results indicate a protective role for a Th1-dominated response, independent of antibody production, in chronic P. aeruginosa lung infection in CF. 相似文献
853.
OBJECTIVE: To examine whether young adults have stereotypical beliefs toward children who have been treated for cancer. METHODS: Undergraduate participants read a vignette describing a child labeled either healthy (HL), in remission from cancer and no longer undergoing treatment (RCL), or in remission and still undergoing treatment (RCTL) and rated the child on the Ratings of the Child Questionnaire (ROCQ). Univariate and multivariate analyses of variance were conducted. RESULTS: Participants rated the HL child more positively than the RCL or RCTL child; the RCL and RCTL child ratings did not differ. Females evaluated the child more positively than did males. CONCLUSIONS: These results support previous findings of a childhood cancer stereotype. However, effect sizes were small, which may indicate a weak stereotype with these specific participants. 相似文献
854.
Caryn Lerman Janet Seay Andrew Balshem Janet Audrain 《American journal of medical genetics. Part A》1995,57(3):385-392
The recent cloning of a breast-ovarian cancer susceptibility gene (BRCA1), and determination of the locus of a related gene (BRCA2), offers potential for clinical genetic testing for breast cancer susceptibility. This study examined interest in and expectations about an impending genetic test among first-degree relatives (FDRs) of breast cancer patients. One hundred five females completed two structured telephone interviews to assess demographics, breast cancer risk factors, psychological factors, and attitudes about genetic testing for breast cancer susceptibility. Overall, 91% of FDRs said that they would want to be tested, 4% said they would not, and 5% were uncertain. The most commonly cited reasons for wanting genetic testing were to learn about one's children's risk, to increase use of cancer screening tests, and to take better care of oneself. Women with less formal education were motivated by childbearing decisions and future planning to a greater degree than were women with education beyond high school. Most women anticipated a negative psychological impact of positive test results, involving increased anxiety (83%), depression (80%), and impaired quality of life (46%). In addition, 72% of women indicated that they would still worry if they tested negative. In multivariate regression analysis, level of baseline depression was the strongest predictor of an anticipated negative impact of genetic testing (Beta =.15; P,.0001). These results suggest that the demand for genetic testing for breast cancer susceptibility may be great, even among women who are not likely to have predisposing mutations. Prior to widespread availability of such testing, it will be critical to develop informed consent protocols to educate individuals about the benefits and limitations of predictive testing for this multifactorial disease. © 1995 Wiley-Liss, Inc. 相似文献
855.
《Acta histochemica》2022,124(4):151895
Cancer is a disease characterised by abnormal cell growth that can invade or spread to other regions of the body. Organoids are three-dimensional ex vivo tissue cultures made from embryonic stem cells, induced pluripotent stem cells, progenitor cells or tissue that serve as a physiological model for cancer research. These are designed to recapitulate the in vivo properties of tumours. Importantly, effective recapitulation of the structure of tissues and function is believed to predict patient response, allowing for the creation of personalised therapy in a timely manner that may be used in the clinic. This Review discusses the pre-clinical model and different types of human organoids as models for the development of high throughput drug screening and also aims to highlight how organoids are shaping the future of cancer research. 相似文献
856.
229 stomachs resected for duodenal and gastric ulcer and carcinoma were examined with special regard to the morphological and histochemical pattern of intestinal metaplasia (IM). The results of qualitative and semiquantitative studies were analysed statistically. Whereas duodenal and gastric ulcer cases are best discriminated by the presence or absence of IM, the strongest discriminating factor between carcinoma and gastric ulcer is the content of goblet cells in metaplastic crypts. Metaplastic crypts lined exclusively with goblet cells producing sulfated acid glycoproteins could be identified in more than one third of the cancer cases. The increase in goblet cells coincides with a loss of the more differentiated cells in the metaplastic glands, such as enterocytes, APUD cells, or Paneth cells. This "enterocoli metaplasia" seems to be specific for cancer bearing mucosa and occurs more often in cancer of intestinal type; it may represent a form of a derepressive dedifferentiation. The significance of enterocoli metaplasia as a premalignant lesion remains to be elucidated. 相似文献
857.
Expression of vascular endothelial growth factor receptor 3 in blood and lymphatic vessels of lung adenocarcinoma 总被引:6,自引:0,他引:6
Vascular endothelial growth factor receptor 3 (VEGFR-3) has been proposed as a marker for lymphatic endothelial cells. This study investigated the expression of VEGFR-3 in the tumour vessels of lung adenocarcinoma and evaluated whether VEGFR-3 staining was useful for identifying lymphatic vessels within the tumour stroma. It also explored whether active growth of lymphatic vessels occurred in lung adenocarcinoma. Formalin-fixed, paraffin-embedded specimens obtained from 60 cases of lung adenocarcinoma, including five cases of pure bronchiolo-alveolar carcinoma (BAC) without stromal, vascular, and pleural invasion, were examined. No VEGFR-3-positive vessels were observed in pure BAC, but varying numbers of VEGFR-3-positive vessels were found in 39 of 55 (70.9%) invasive adenocarcinomas. A comparison of serial sections stained for VEGFR-3, CD31, and laminin-1 showed that most of the VEGFR-3-positive vessels appeared to be blood vessels (CD31-positive, laminin-1-positive), but some had the characteristics of lymphatic vessels (variable staining for CD31, little or no staining for laminin-1). VEGFR-3 staining highlighted lymphatic invasion by cancer cells; this invasion could not be detected by CD31 or haematoxylin and eosin (H&E) staining. Active growth of lymphatic vessels (as indicated by nuclear Ki-67 labelling of the endothelium) was observed in five tumours, four of which showed a high level of lymphatic invasion by cancer cells. It was concluded that VEGFR-3 immunostaining did not discriminate clearly between vascular and lymphatic endothelial cells, since expression of VEGFR-3 can be up-regulated in tumour blood vessels. However, VEGFR-3 staining combined with laminin-1 and CD31 staining would be useful for identifying lymphatic vessels and their invasion by tumour cells in a more objective way. Finally, proliferation of lymphatic endothelial cells may occur in association with lymphatic invasion by cancer cells. 相似文献
858.
Lohm S Peduto-Eberl L Lagadec P Renggli-Zulliger N Dudler J Jeannin JF Juillerat-Jeanneret L 《Clinical & experimental metastasis》2005,22(4):341-349
It is recognised that stromal cells determine cancer progression. We have previously shown that active TGFβ produced by rat colon carcinoma cells modulated NO production in rat endothelial cells. To elucidate the role of TGFβ and NO in the mechanisms of interaction of colon carcinoma cells with stromal cells and in cancer progression, we transfected
REGb cells, a regressive colon carcinoma clone secreting latent TGFβ, with a cDNA encoding for a constitutively-secreted active TGFβ. Out of 20 injected rats only one tumour progressed, which was resected and sub-cultured (ReBeta cells). ReBeta cells secreted
high levels of active TGFβ. The adhesive properties of REGb and Rebeta cells to endothelial cells were similar, showing that the secretion of active
TGFβ is not involved in tumour cell adhesion to endothelial cells. ReBeta, but not REGb, cell culture supernatants inhibited cytokine-dependent
NO secretion by endothelial cells, but inhibition of NO production was similar in co-cultures of REGb or ReBeta cells with
endothelial cells. Therefore, secretion of active TGFβ regulated endothelial NO synthase activity when tumour cells were distant from, but not in direct contact with, endothelial
cells. However, only ReBeta cells inhibited cytokine-dependent secretion of NO in coculture with macrophages, indicating that
the active-TGFβ–NO axis confers an advantage for tumour cells in their interaction with macrophages rather than endothelial cells in cancer
progression. 相似文献
859.
Tangir J Bonafé N Gilmore-Hebert M Henegariu O Chambers SK 《Clinical & experimental metastasis》2004,21(6):477-483
The aggressive behavior of breast cancer cells can at times be modulated by hormonal mechanisms. Exposure to glucocorticoids
(GC) has been shown to stimulate the invasiveness, motility and adhesiveness of breast cancer cells containing the glucocorticoid
receptor. This is largely explained by GC-associated overexpression of the c-fms proto-oncogene, which encodes the receptor for the colony stimulating factor-1 (CSF-1). Our objective is to investigate additional
GC-associated genetic alterations that could modulate c-fms related malignant behavior in breast cancer cells. A microarray technique using an oligonucleotide array representing 16,700
known expressed human genes was used to analyze the gene expression profile of breast cancer cells exposed to dexamethasone
(Dex) or vehicle. Results were confirmed by western blot analysis. Six genes were found to be consistently differentially
overexpressed in the Dex-exposed cells compared to control. We focused on serum-glucose kinase 1 (SGK1), a serine-threonine
kinase known to be involved in intracellular signal transduction pathways and induced by GC and serum. An adhesion assay was
performed on extracellular matrix after exposing the breast cancer cells to Dex, CSF-1 or to Dex or CSF-1 plus LY294002, a
functional inhibitor of SGK1 action. Exposure to LY294002 significantly decreased both CSF-1 and Dex-induced adhesiveness
to the level of control cells. SGK1 may act as a downstream intracellular regulator of c-fms, particularly of c-fms-induced adhesiveness of breast cancer cells after exposure to GC or CSF-1. This finding may have implications for potential
therapeutic interventions aimed at decreasing the aggressiveness of breast cancer cells.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
860.
Objective To investigate whether FK506 (tacrolimus) can inhibit Fas- or A23187-induced interleukin (IL)-8 expression and cell death
in A549 human alveolar epithelial cells, plus Fas-mediated acute lung injury in vivo.
Methods Assays for IL-8, cell death, and caspase-3 activity were performed. A549 cells were treated with 25 μmol A23187 or 0.2 μg/ml
agonistic anti-Fas antibody plus 5 ng/ml interferon-gamma (IFN-γ). Tacrolimus was treated at 0.1–10 ng/ml. For in vivo experiment,
agonistic anti-Fas antibody (Jo2) at 2.5 μg/g was intratracheally instilled into C57BL/6 mice. Neutrophils and protein contents
in bronchoalveolar lavage (BAL) fluid were measured within 24 h of instillation. Mice were orally treated with 32 mg/kg of
tacrolimus 24 h and 1 h prior to instillation.
Results Both Fas and A23187 caused significant IL-8 expression and cell death in A549 cells. Tacrolimus inhibited A23187-induced IL-8
expression alone while it protected all Fas-mediated responses. Mice instilled intratracheally with Jo2 at 2.5 μg/g had significant
increases in neutrophils, protein contents in BAL fluid and in expression of chemoattractants for neutrophils. These increases
were reversed by tacrolimus.
Conclusions Tacrolimus serves as a therapeutic option for improving lung injury through inhibition of Fas-mediated inflammation.
Received 7 November 2005; returned for revision 28 December 2005; accepted by G. Wallace 2 February 2006 相似文献