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101.
CHO-K1, COS-7, and Rat2 fibroblast cell lines are generally believed to be devoid of estrogen receptors (ERs) and have been widely used to study the functions of ER-alpha and ER-beta after transfection of their cDNAs. Numerous studies have demonstrated that transfected ER-alpha or ER-beta mediates estradiol-induced activation of multiple signaling pathways, including the MAPK/ERK pathways. We report here for the first time that both 17alpha-estradiol and 17beta-estradiol elicit activation of MAPK/ERK in native, nontransfected CHO-K1, COS-7, and Rat2 fibroblast cell lines. We further report that, contrary to the generally held belief, these cell lines are not unresponsive to estradiol in their native, nontransfected state, and that this estrogen responsiveness is associated with estrogen binding. Using multiple ER antibodies, we failed to find ER-alpha or ER-beta isoforms or even ER-X. In view of these findings, researchers, using such cells as models to investigate mechanisms of estrogen action, must always take into account the existence of endogenous estrogen binding proteins other than ER-alpha, ER-beta, or ER-X.  相似文献   
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Background A rapid, accurate, noninvasive means of predicting the likelihood of failure to achieve Thrombolysis In Myocardial Infarction (TIMI) grade 3 flow within 90 minutes after the start of fibrinolysis with streptokinase could help to identify patients who might benefit from additional therapies that aim to preserve myocytes. Methods We measured ST recovery, which was assessed as the sum of ST deviation on a 12-lead electrocardiogram, and blood levels of the myocardial proteins, troponin T, creatine kinase myocardial band (CK-MB), and myoglobin before and 60 minutes after commencing streptokinase infused for 30 to 60 minutes in 107 patients, who presented within 12 hours of symptom onset and underwent angiography at 90 minutes. Results At 90 minutes, 56% of patients (95% CI 46-66) had TIMI-3 flow. The baseline levels of troponin T, CK-MB, and myoglobin were more commonly below the discrimination values in patients with TIMI-3 flow than in patients without TIMI-3 flow (all P < .005). On multivariate analysis, the factors associated with failure to achieve TIMI-3 flow were ST recovery of <70% (P = .009), a 60-minute/baseline troponin T ratio of ≤5 (P = .0004), a baseline CK-MB level of >4 μg/L (P = .039), or a baseline myoglobin level of >85 μg/L (P = .048). Age and a history of myocardial infarction were added into the multivariate model, and a risk score was developed to predict the likelihood of failure to achieve TIMI-3 flow. A score of ≤2 excluded failure to achieve TIMI-3 flow with 96% accuracy, and a score of ≥7 predicted failure to achieve TIMI-3 flow with 90% accuracy. Conclusion Failure to achieve TIMI-3 flow in the infarct-related artery within 90 minutes after the start of fibrinolysis can be accurately predicted at approximately 60 minutes by a score incorporating clinical variables, ST recovery, and the 60-minute/baseline ratios of troponin T, CK-MB, and/or myoglobin levels. This score may facilitate triage of patients at 60 minutes after fibrinolysis to additional reperfusion therapies. (Am Heart J 2003;145:508-14.)  相似文献   
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Three National Health and Nutrition Examination Surveys were conducted in the United States between 1971 and 1994 to provide data on the nutritional and health status of the population and on specific target conditions. This article describes features of the surveys and provides examples of research on musculoskeletal disorders that used the survey data.  相似文献   
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Hematopoietic stem cells reside in the bone marrow, where they generate the effector cells that drive immune responses. However, in response to inflammation, some hematopoietic stem and progenitor cells (HSPCs) are recruited to tissue sites and undergo extramedullary hematopoiesis. Contrasting with this paradigm, here we show residence and differentiation of HSPCs in healthy gingiva, a key oral barrier in the absence of overt inflammation. We initially defined a population of gingiva monocytes that could be locally maintained; we subsequently identified not only monocyte progenitors but also diverse HSPCs within the gingiva that could give rise to multiple myeloid lineages. Gingiva HSPCs possessed similar differentiation potentials, reconstitution capabilities, and heterogeneity to bone marrow HSPCs. However, gingival HSPCs responded differently to inflammatory insults, responding to oral but not systemic inflammation. Combined, we highlight a novel pathway of myeloid cell development at a healthy barrier, defining a gingiva-specific HSPC network that supports generation of a proportion of the innate immune cells that police this barrier.  相似文献   
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In epilepsy diagnosis or epileptic seizure detection, much effort has been focused on finding effective combination of feature extraction and classification methods. In this paper, we develop a wavelet-based sparse functional linear model for representation of EEG signals. The aim of this modeling approach is to capture discriminative random components of EEG signals using wavelet variances. To achieve this goal, a forward search algorithm is proposed for determination of an appropriate wavelet decomposition level. Two EEG databases from University of Bonn and University of Freiburg are used for illustration of applicability of the proposed method to both epilepsy diagnosis and epileptic seizure detection problems. For this data considered, we show that wavelet-based sparse functional linear model with a simple classifier such as 1-NN classification method leads to higher classification results than those obtained using other complicated methods such as support vector machine. This approach produces a 100 % classification accuracy for various classification tasks using the EEG database from University of Bonn, and outperforms many other state-of-the-art techniques. The proposed classification scheme leads to 99 % overall classification accuracy for the EEG data from University of Freiburg.  相似文献   
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Overactive B cells, abnormally activated T cells and inappropriate handling of cellular debris by the innate immune system are central in the pathogenesis of systemic lupus erythematosus (SLE). Genetic studies in SLE patients have unraveled allelic variations in genes encoding key molecules that control inter- and intra-cellular signaling and play a role in the abnormal handling of apoptotic material. Despite recent breakthroughs though, it is still unclear how exactly genes and environment interact to produce the characteristic immune dysregulation in SLE.  相似文献   
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The goal of controlling ovarian cancer metastasis formation has elicited considerable interest in identifying the tissue microenvironments involved in cancer cell colonization of the omentum. Omental adipose is a site of prodigious metastasis in both ovarian cancer models and clinical disease. This tissue is unusual for its milky spots, comprised of immune cells, stromal cells, and structural elements surrounding glomerulus-like capillary beds. The present study shows the novel finding that milky spots and adipocytes play distinct and complementary roles in omental metastatic colonization. In vivo assays showed that ID8, CaOV3, HeyA8, and SKOV3ip.1 cancer cells preferentially lodge and grow within omental and splenoportal fat, which contain milky spots, rather than in peritoneal fat depots. Similarly, medium conditioned by milky spot–containing adipose tissue caused 75% more cell migration than did medium conditioned by milky spot–deficient adipose. Studies with immunodeficient mice showed that the mouse genetic background does not alter omental milky spot number and size, nor does it affect ovarian cancer colonization. Finally, consistent with the role of lipids as an energy source for cancer cell growth, in vivo time-course studies revealed an inverse relationship between metastatic burden and omental adipocyte content. Our findings support a two-step model in which both milky spots and adipose have specific roles in colonization of the omentum by ovarian cancer cells.CME Accreditation Statement: This activity (“ASIP 2013 AJP CME Program in Pathogenesis”) has been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education (ACCME) through the joint sponsorship of the American Society for Clinical Pathology (ASCP) and the American Society for Investigative Pathology (ASIP). ASCP is accredited by the ACCME to provide continuing medical education for physicians.The ASCP designates this journal-based CME activity (“ASIP 2013 AJP CME Program in Pathogenesis”) for a maximum of 48 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.CME Disclosures: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.It is estimated that 22,240 women will be diagnosed with and 14,030 women will die of cancer of the ovary in 2013 (http://seer.cancer.gov/csr/1975_2009_pops09, last accessed June 18, 2013). The majority of patients present with metastases or eventually die of metastatic disease within the abdominal cavity. After escape from the primary tumor, ovarian cancer cells in the peritoneal fluid have access to and can potentially lodge within a variety of tissues.1,2 In both clinical disease and experimental models, however, the omentum is the site of prodigious metastasis formation.3–6 Thus, attachment of ovarian cancer cells to the omentum represents an early step in the development of widespread peritoneal disease.7,8 Although the importance of the omentum is widely acknowledged, there still is no consensus on its role in metastasis formation. This raises the question of what components of the omental tissue microenvironment participate in, or facilitate, ovarian cancer metastatic colonization.Studies of omental function date back to the early 19th century. Jobert de Lamballe, a 19th-century surgeon in France, was reportedly the first to recognize the curious ability of this organ to fight infection and form adhesions to help control injuries.9 After nearly two centuries of investigation, a great deal is known about the physiology and surgical applications of the omentum.9–12 As the central regulator of peritoneal homeostasis, its functions include regulating fluid and solute transport, sensing and repairing injuries, promoting angiogenesis, fighting infection, serving as a source of stem cells, producing regulatory molecules, and storing and supplying lipids. These diverse functions are conferred by the cellular composition and architecture characteristic of human omenta.Aside from the clear collagenous membrane that acts as a scaffold for the organ, the majority of the omentum is composed of bands of adipose tissue that contain adipocytes, blood and lymph vessels, immune cells, stromal cells, and connective matrix components that lie beneath an irregular mesothelium.13 In general, adipocytes have a variety of functions, ranging from lipid storage to production of endocrine molecules, and can serve as an integrating hub for inflammation, metabolism, and immunity.2,14–23 A distinctive feature of the omental vasculature is the presence of numerous branching blood vessels ending in tortuous glomerulus-like capillary beds near the tissue periphery.24–28 Immune cells aggregate around and within these capillary beds to form milky spots, which are the major immune structure for host defense of the peritoneal cavity.24,29–36 In milky spots, both the endothelial lining of the capillaries and the overlying mesothelium are specially adapted to facilitate transmigration of immune cells.24,37,38 Additional structural elements include plasmocytes, fibroblasts, and mesenchymal cells, as well as collagen and reticular and elastic fibers.29,34,37,39A comprehensive literature review showed that studies examining the role of the omentum in metastasis focus on the contribution of its individual components, and not on the tissue as a whole. In our view, results from the majority of studies support models in which ovarian cancer metastatic colonization is driven either purely by milky spots or purely by adipocytes. The milky spot–driven model is based on a large body of in vivo data showing that, on intraperitoneal injection, cancer cells rapidly and specifically localize, invade, and proliferate within omental milky spots.3,6,24,28,40–44 In contrast, the adipocyte-driven model is based on the observation that, in its resting state, the omentum is composed predominantly of adipose and that cultured adipocytes can produce adipokines capable of promoting ovarian cancer cell migration and invasion in vitro.45 Adipocytes can also provide a proliferative advantage by transferring fatty acids to ovarian cancer cells.45 Although both models have clear strengths, neither addresses the intimate and dynamic interaction among milky spots, surrounding adipocytes, and other components of omental tissues.Taking tissue architecture and function as a guide, we propose that an alternative, more fully integrated model of metastatic colonization is needed. To test this idea, we identified peritoneal fat depots (omentum, mesentery, and uterine, gonadal, and splenoportal fat) that are accessible to ovarian cancer cells after intraperitoneal injection.2 Of these, the omentum and splenoportal fat are reported to contain milky spot structures.24,46 We reasoned that a comparison of peritoneal adipose that either contains or lacks milky spots could be used to determine the contributions of adipocytes and milky spots to the lodging and progressive growth of ovarian cancer cells in physiologically relevant tissues. In vivo studies using a panel of ovarian cancer cell lines showed that milky spots dramatically enhance early cancer cell lodging on peritoneal adipose tissues. Consistent with this finding, conditioned medium from milky spot–containing adipose tissue had a significantly increased ability to direct cell migration, compared with conditioned medium from milky spot–deficient adipose tissue. Studies using a panel of immunodeficient mice showed that the number and size of omental milky spots is not dependent on the mouse genetic background and, similarly, that ovarian cancer cell colonization does not depend on the immune composition of the milky spot. Finally, consistent with the role for lipids as an energy source for ovarian cancer cell growth, in vivo time-course studies revealed an inverse relationship between metastatic burden and adipocyte content in the omentum. Our findings support a two-step model in which both milky spots and adipose have specific roles in colonization of the omentum by ovarian cancer cells.  相似文献   
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