35 research outputs found
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Inhibiting Vimentin or beta 1-integrin Reverts Prostate Tumor Cells in IrECM and Reduces Tumor Growth
Prostate epithelial cells grown embedded in laminin-rich extracellular matrix (lrECM) undergo morphological changes that closely resemble their architecture in vivo. In this study, growth characteristics of three human prostate epithelial sublines derived from the same cellular lineage, but displaying different tumorigenic and metastatic properties in vivo, were assessed in three-dimensional (3D) lrECM gels. M12, a highly tumorigenic and metastatic subline, was derived from the parental prostate epithelial P69 cell line by selection in nude mice and found to contain a deletion of 19p-q13.1. The stable reintroduction of an intact human chromosome 19 into M12 resulted in a poorly tumorigenic subline, designated F6. When embedded in lrECM gels, the nontumorigenic P69 line produced acini with clearly defined lumena. Immunostaining with antibodies to {beta}-catenin, E-cadherin or {alpha}6-, {beta}4- and {beta}1-integrins showed polarization typical of glandular epithelium. In contrast, the metastatic M12 subline produced highly disorganized cells with no evidence of polarization. The F6 subline reverted to acini-like structures exhibiting basal polarity marked with integrins. Reducing either vimentin levels via siRNA interference or {beta}1-integrin expression by the addition of the blocking antibody, AIIB2, reorganized the M12 subline into forming polarized acini. The loss of vimentin significantly reduced M12-Vim tumor growth when assessed by subcutaneous injection in athymic mice. Thus, tumorigenicity in vivo correlated with disorganized growth in 3D lrECM gels. These studies suggest that the levels of vimentin and {beta}1-integrin play a key role in the homeostasis of the normal acini in prostate and that their dysregulation may lead to tumorigenesis
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Inhibition of vimentin or B1 integrin reverts morphology of prostate tumor cells grown in laminin-rich extracellular matrix gels and reduces tumor growth in vivo
Prostate epithelial cells grown embedded in laminin-rich extracellular matrix (lrECM) undergo morphologic changes that closely resemble their architecture in vivo. In this study, growth characteristics of three human prostate epithelial sublines derived from the same cellular lineage, but displaying different tumorigenic and metastatic properties in vivo, were assessed in three-dimensional lrECM gels. M12, a highly tumorigenic and metastatic subline, was derived from the immortalized, prostate epithelial P69 cell line by selection in athymic, nude mice and found to contain a deletion of 19p-q13.1. The stable reintroduction of an intact human chromosome 19 into M12 resulted in a poorly tumorigenic subline, designated F6. When embedded in lrECM gels, the parental, nontumorigenic P69 line produced acini with clearly defined lumena. Immunostaining with antibodies to {beta}-catenin, E-cadherin, or {alpha}6 and {beta}1 integrins showed polarization typical of glandular epithelium. In contrast, the metastatic M12 subline produced highly disorganized cells with no evidence of polarization. The F6 subline reverted to acini-like structures exhibiting basal polarity marked with integrins. Reducing either vimentin levels via small interfering RNA interference or the expression of {alpha}6 and {beta}1 integrins by the addition of blocking antibodies, reorganized the M12 subline into forming polarized acini. The loss of vimentin significantly reduced M12-Vim tumor growth when assessed by s.c. injection in athymic mice. Thus, tumorigenicity in vivo correlated with disorganized growth in three-dimensional lrECM gels. These studies suggest that the levels of vimentin and {beta}1 integrin play a key role in the homeostasis of the normal acinus in prostate and that their dysregulation may lead to tumorigenesis. [Mol Cancer Ther 2009;8(3):499-508]
Randomised controlled trial of food elimination diet based on IgG antibodies for the prevention of migraine like headaches
<p>Abstract</p> <p>Background</p> <p>Research suggests that food intolerance may be a precipitating factor for migraine like headaches.</p> <p>Aim</p> <p>To evaluate the effectiveness of the ELISA (Enzyme Linked Immuno-Sorbent Assay) Test and subsequent dietary elimination advice for the prevention of migraine like headaches.</p> <p>Design</p> <p>Randomised controlled trial.</p> <p>Setting</p> <p>Community based volunteers in the UK.</p> <p>Participants</p> <p>Volunteers who met the inclusion criteria for migraine like headaches and had one or more food intolerance were included in the study. Participants received either a true diet (n = 84) or a sham diet (n = 83) sheet. Participants were advised to remove the intolerant foods from their diet for 12 weeks.</p> <p>Main outcome measures</p> <p>Number of headache days over a 12 week period (item A MIDAS questionnaire). Other measures includes the total MIDAS score and total HIT-6 score.</p> <p>Results</p> <p>The results indicated a small decrease in the number of migraine like headaches over 12 weeks, although this difference was not statistically significant (IRR 1.15 95% CI 0.94 to 1.41, p = 0.18). At the 4 week assessment, use of the ELISA test with subsequent diet elimination advice significantly reduced the number of migraine like headaches (IRR 1.23 95%CI 1.01 to 1.50, p = 0.04). The disability and impact on daily life of migraines were not significantly different between the true and sham diet groups.</p> <p>Conclusions</p> <p>Use of the ELISA test with subsequent diet elimination advice did not reduce the disability or impact on daily life of migraine like headaches or the number of migraine like headaches at 12 weeks but it did significantly reduce the number of migraine like headaches at 4 weeks.</p> <p>Trial registration number</p> <p>ISRCTN: <a href="http://www.controlled-trials.com/ISRTCN89559672">ISRTCN89559672</a></p
All-arthroscopic versus mini-open repair of small or moderate-sized rotator cuff tears: A protocol for a randomized trial [NCT00128076]
BACKGROUND: Rotator cuff tears are the most common source of shoulder pain and disability. Only poor quality studies have compared mini-open to arthroscopic repair, leaving surgeons with inadequate evidence to support optimal, minimally-invasive repair. METHODS/DESIGN: This randomized, multi-centre, national trial will determine whether an arthroscopic or mini-open repair provides better quality of life for patients with small or moderate-sized rotator cuff tears. A national consensus meeting of investigators in the Joint Orthopaedic Initiative for National Trials of the Shoulder (JOINTS Canada) identified this question as the top priority for shoulder surgeons across Canada. The primary outcome measure is a valid quality-of-life scale (Western Ontario Rotator Cuff (WORC)) that addresses 5 domains of health affected by rotator cuff disease. Secondary outcomes will assess rotator cuff functionality (ROM, strength, Constant score), secondary dimensions of health (general health status (SF-12) and work limitations), and repair integrity (MRI). Outcomes are measured at baseline, at 6 weeks, 3, 6, 12, and 24 months post-operatively by blinded research assistants and musculoskeletal radiologists. Patients (n = 250) with small or medium-sized cuff tears identified by clinical examination and MRI who meet eligibility criteria will be recruited. This sample size will provide 80% power to statistically detect a clinically important difference of 20% in WORC scores between procedures after controlling for baseline WORC score (α = 0.05). A central methods centre will manage randomization, data management, and monitoring under supervision of experienced epidemiologists. Surgeons will participate in either conventional or expertise-based designs according to defined criteria to avoid biases from differential surgeon expertise. Mini-open or all-arthroscopic repair procedures will be performed according to a standardized protocol. Central Adjudication (of cases), Trial Oversight and Safety Committees will monitor trial conduct. We will use an analysis of covariance (ANCOVA), where the baseline WORC score is used as a covariate, to compare the quality of life (WORC score) at 2 years post-operatively. As a secondary analysis, we will conduct the same statistical test but will include age and tear size as covariates with the baseline score. Enrollment will require 2 years and follow-up an additional 2 years. The trial will commence when funding is in place. DISCUSSION: These results will have immediate impact on the practice behaviors of practicing surgeons and surgical trainees at JOINTS centres across Canada. JOINTS Canada is actively engaged in knowledge exchange and will publish and present findings internationally to facilitate wider application. This trial will establish definitive evidence on this question at an international level
Disease in a dynamic landscape: Host behavior and wildfire reduce amphibian chytrid infection
Disturbances are often expected to magnify effects of disease, but these effects may depend on the ecology, behavior, and life history of both hosts and pathogens. In many ecosystems, wildfire is the dominant natural disturbance and thus could directly or indirectly affect dynamics of many diseases. To determine how probability of infection by the aquatic fungus Batrachochytrium dendrobatidis (Bd) varies relative to habitat use by individuals, wildfire, and host characteristics, we sampled 404 boreal toads (Anaxyrus boreas boreas) across Glacier National Park, Montana (USA). Bd causes chytridiomycosis, an emerging infectious disease linked with widespread amphibian declines, including the boreal toad. Probability of infection was similar for females and the combined group of males and juveniles. However, only 9% of terrestrial toads were infected compared to \u3e30% of aquatic toads, and toads captured in recently burned areas were half as likely to be infected as toads in unburned areas. We suspect these large differences in infection reflect habitat choices by individuals that affect pathogen exposure and persistence, especially in burned forests where warm, arid conditions could limit Bd growth. Our results show that natural disturbances such as wildfire and the resulting diverse habitats can influence infection across large landscapes, potentially maintaining local refuges and host behaviors that facilitate evolution of disease resistance
Identification of a Novel Cell Death Receptor Mediating IGFBP-3-induced Anti-tumor Effects in Breast and Prostate Cancer*
Insulin-like growth factor-binding protein-3 (IGFBP-3), a major regulator of endocrine actions of IGFs, is a p53-regulated potent apoptotic factor and is significantly suppressed in a variety of cancers. Recent epidemiologic studies suggest that IGFBP-3 contributes to cancer risk protection in a variety of cancers, and a polymorphic variation of IGFBP-3 influences cancer risk, although other studies vary in their conclusions. Some antiproliferative actions of IGFBP-3 have been reported to be independent of IGFs, but the precise biochemical/molecular mechanisms of IGF-independent, antiproliferative actions of IGFBP-3 are largely unknown. Here we report a new cell death receptor, IGFBP-3R, that is a single-span membrane protein and binds specifically to IGFBP-3 but not other IGFBP species. Expression analysis of IGFBP-3 and IGFBP-3R indicates that the IGFBP-3/IGFBP-3R axis is impaired in breast and prostate cancer. We also provide evidence for anti-tumor effect of IGFBP-3R in vivo using prostate and breast cancer xenografts in athymic nude mice. Further in vitro studies demonstrate that IGFBP-3R mediates IGFBP-3-induced caspase-8-dependent apoptosis in various cancer cells. Knockdown of IGFBP-3R attenuated IGFBP-3-induced caspase activities and apoptosis, whereas overexpression of IGFBP-3R enhanced IGFBP-3 biological effects. IGFBP-3R physically interacts and activates caspase-8, and knockdown of caspase-8 expression or activity inhibited IGFBP-3/IGFBP-3R-induced apoptosis. Here, we propose that IGFBP-3R represents a novel cell death receptor and is essential for the IGFBP-3-induced apoptosis and tumor suppression. Thus, the IGFBP-3/IGFBP-3R axis may provide therapeutic and prognostic value for the treatment of cancer
Health Care for Homeless Women: Unmet Needs and Barriers to Care
OBJECTIVE: Homelessness is a significant and growing problem in the United States. Women and families are the fastest growing segments of the homeless population. Homelessness increases the risk of having health problems and encountering barriers to care. This study determines how much perceived unmet need for medical care there is among homeless women, what homeless women perceive to be barriers to health care, and how barriers and other factors are associated with unmet needs. DESIGN: Cross-sectional study of homeless women, utilizing structured interviews. SETTING AND PARTICIPANTS: Community-based probability sample of 974 homeless women aged 15 to 44 years. MAIN OUTCOME MEASURES: Perceived unmet need for medical care in the past 60 days. Relationship between unmet need and demographic variables, place of stay, source of health care, insurance, and perceived barriers to care. RESULTS: Of the 974 women, 37% reported unmet need for medical care. Controlling for other factors, the odds of unmet need were lower among those with a regular source of care (odds ratio [OR] to .35, 95% confidence interval [CI], .21 to 58), while having health insurance was not significantly associated. The odds of unmet need were higher among those who experienced the barriers: not knowing where to go (OR 2.27, 95% CI, 1.40 to 3.69), long office waiting times (OR 1.89, 95% CI 1.27 to 2.83) and being too sick to seek care (OR 2.03, 95% CI, 1.14 to 3.62). CONCLUSIONS: There is significant unmet need for medical care among homeless women. Having a regular source of care was more important than health insurance in lowering the odds of unmet need. Homeless women must be educated regarding sources of care, and clinics serving the homeless must decrease waiting times