34 research outputs found
Non-specific interstitial pneumonia in cigarette smokers: a CT study
The goal of this study was to seek indirect evidence that smoking is an aetiological factor in some patients with non-specific interstitial pneumonia (NSIP). Ten current and eight ex-smokers with NSIP were compared to controls including 137 current smokers with no known interstitial lung disease and 11 non-smokers with NSIP. Prevalence and extent of emphysema in 18 smokers with NSIP were compared with subjects meeting GOLD criteria for chronic obstructive pulmonary disease (COPD; group A; n = 34) and healthy smokers (normal FEV1; group B; n = 103), respectively. Emphysema was present in 14/18 (77.8%) smokers with NSIP. Emphysema did not differ in prevalence between NSIP patients and group A controls (25/34, 73.5%), but was strikingly more prevalent in NSIP patients than in group B controls (18/103, 17.5%, P < 0.0005). On multiple logistic regression, the likelihood of emphysema increased when NSIP was present (OR = 18.8; 95% CI = 5.3–66.3; P < 0.0005) and with increasing age (OR = 1.04; 95% CI = 0.99–1.11; P = 0.08). Emphysema is as prevalent in smokers with NSIP as in smokers with COPD, and is strikingly more prevalent in these two groups than in healthy smoking controls. The association between NSIP and emphysema provides indirect support for a smoking pathogenesis hypothesis in some NSIP patients
Global Methylation Patterns in Idiopathic Pulmonary Fibrosis
BACKGROUND: Idiopathic Pulmonary Fibrosis (IPF) is characterized by profound changes in the lung phenotype including excessive extracellular matrix deposition, myofibroblast foci, alveolar epithelial cell hyperplasia and extensive remodeling. The role of epigenetic changes in determining the lung phenotype in IPF is unknown. In this study we determine whether IPF lungs exhibit an altered global methylation profile.\ud
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METHODOLOGY/PRINCIPAL FINDINGS: Immunoprecipitated methylated DNA from 12 IPF lungs, 10 lung adenocarcinomas and 10 normal histology lungs was hybridized to Agilent human CpG Islands Microarrays and data analysis was performed using BRB-Array Tools and DAVID Bioinformatics Resources software packages. Array results were validated using the EpiTYPER MassARRAY platform for 3 CpG islands. 625 CpG islands were differentially methylated between IPF and control lungs with an estimated False Discovery Rate less than 5%. The genes associated with the differentially methylated CpG islands are involved in regulation of apoptosis, morphogenesis and cellular biosynthetic processes. The expression of three genes (STK17B, STK3 and HIST1H2AH) with hypomethylated promoters was increased in IPF lungs. Comparison of IPF methylation patterns to lung cancer or control samples, revealed that IPF lungs display an intermediate methylation profile, partly similar to lung cancer and partly similar to control with 402 differentially methylated CpG islands overlapping between IPF and cancer. Despite their similarity to cancer, IPF lungs did not exhibit hypomethylation of long interspersed nuclear element 1 (LINE-1) retrotransposon while lung cancer samples did, suggesting that the global hypomethylation observed in cancer was not typical of IPF.\ud
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CONCLUSIONS/SIGNIFICANCE: Our results provide evidence that epigenetic changes in IPF are widespread and potentially important. The partial similarity to cancer may signify similar pathogenetic mechanisms while the differences constitute IPF or cancer specific changes. Elucidating the role of these specific changes will potentially allow better understanding of the pathogenesis of IPF.\ud
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Functional Wnt Signaling Is Increased in Idiopathic Pulmonary Fibrosis
BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease, characterized by distorted lung architecture and loss of respiratory function. Alveolar epithelial cell injury and hyperplasia, enhanced extracellular matrix deposition, and (myo)fibroblast activation are features of IPF. Wnt/beta-catenin signaling has been shown to determine epithelial cell fate during development. As aberrant reactivation of developmental signaling pathways has been suggested to contribute to IPF pathogenesis, we hypothesized that Wnt/beta-catenin signaling is activated in epithelial cells in IPF. Thus, we quantified and localized the expression and activity of the Wnt/beta-catenin pathway in IPF. METHODOLOGY/PRINCIPAL FINDINGS: The expression of Wnt1, 3a, 7b, and 10b, the Wnt receptors Fzd1-4, Lrp5-6, as well as the intracellular signal transducers Gsk-3beta, beta-catenin, Tcf1, 3, 4, and Lef1 was analyzed in IPF and transplant donor lungs by quantitative real-time (q)RT-PCR. Wnt1, 7b and 10b, Fzd2 and 3, beta-catenin, and Lef1 expression was significantly increased in IPF. Immunohistochemical analysis localized Wnt1, Wnt3a, beta-catenin, and Gsk-3beta expression largely to alveolar and bronchial epithelium. This was confirmed by qRT-PCR of primary alveolar epithelial type II (ATII) cells, demonstrating a significant increase of Wnt signaling in ATII cells derived from IPF patients. In addition, Western blot analysis of phospho-Gsk-3beta, phospho-Lrp6, and beta-catenin, and qRT-PCR of the Wnt target genes cyclin D1, Mmp 7, or Fibronectin 1 demonstrated increased functional Wnt/beta-catenin signaling in IPF compared with controls. Functional in vitro studies further revealed that Wnt ligands induced lung epithelial cell proliferation and (myo)fibroblast activation and collagen synthesis. CONCLUSIONS/SIGNIFICANCE: Our study demonstrates that the Wnt/beta-catenin pathway is expressed and operative in adult lung epithelium. Increased Wnt/beta-catenin signaling may be involved in epithelial cell injury and hyperplasia, as well as impaired epithelial-mesenchymal cross-talk in IPF. Thus, modification of Wnt signaling may represent a therapeutic option in IPF
Fatores associados ao consumo regular de refrigerante não dietético em adultos de Pelotas, RS
OBJECTIVE: To assess factors associated with regular intake of non-diet soft drinks among adults. METHODS: Population-based cross-sectional study including 972 adults (aged 20 to 69) in the city of Pelotas, Southern Brazil, conducted in 2006. The frequency of non-diet soft drink intake in the 12 months prior to the study was evaluated by the question: "In general since lastOBJETIVO: Analizar factores asociados al consumo regular de gaseosas no dietéticas por adultos. MÉTODOS: Estudio transversal de base poblacional con 972 adultos (20 a 69 años) del municipio de Pelotas, Sur de Brasil, realizado en 2006. La frecuencia de consumo en los 12 meses anteriores a la investigación fue medida por medio de la pregunta: "en general desde elOBJETIVO: Analisar fatores associados ao consumo regular de refrigerantes não dietéticos por adultos. MÉTODOS: Estudo transversal de base populacional com 972 adultos (20 a 69 anos) do município de Pelotas, RS, realizado em 2006. A freqüência de consumo nos 12 meses anteriores à pesquisa foi medida por meio da pergunta: "em geral desde
Viruses as co-factors for the initiation or exacerbation of lung fibrosis
Idiopathic pulmonary fibrosis (IPF) remains exactly that. The disease originates from an unknown cause, and little is known about the mechanisms of pathogenesis. While the disease is likely multi-factorial, evidence is accumulating to implicate viruses as co-factors (either as initiating or exacerbating agents) of fibrotic lung disease. This review summarizes the available clinical and experimental observations that form the basis for the hypothesis that viral infections may augment fibrotic responses. We review the data suggesting a link between hepatitis C virus, adenovirus, human cytomegalovirus and, in particular, the Epstein-Barr gammaherpesvirus, in IPF. In addition, we highlight the recent associations made between gammaherpesvirus infection and lung fibrosis in horses and discuss the various murine models that have been used to investigate the contribution of gammaherpesviruses to fibrotic progression. We review the work demonstrating that gammaherpesvirus infection of Th2-biased mice leads to multi-organ fibrosis and highlight studies showing that gammaherpesviral infections of mice either pre- or post-fibrotic challenge can augment the development of fibrosis. Finally, we discuss potential mechanisms whereby viral infections may amplify the development of fibrosis. While none of these studies prove causality, we believe the evidence suggests that viral infections should be considered as potential initiators or exacerbating agents in at least some cases of IPF and thereby justify further study
Idiopathic pulmonary fibrosis
Idiopathic pulmonary fibrosis (IPF) is a non-neoplastic pulmonary disease that is characterized by the formation of scar tissue within the lungs in the absence of any known provocation. IPF is a rare disease which affects approximately 5 million persons worldwide. The prevalence is estimated to be slightly greater in men (20.2/100,000) than in women (13.2/100,000). The mean age at presentation is 66 years. IPF initially manifests with symptoms of exercise-induced breathless and dry coughing. Auscultation of the lungs reveals early inspiratory crackles, predominantly located in the lower posterior lung zones upon physical exam. Clubbing is found in approximately 50% of IPF patients. Cor pulmonale develops in association with end-stage disease. In that case, classic signs of right heart failure may be present. Etiology remains incompletely understood. Some environmental factors may be associated with IPF (cigarette smoking, exposure to silica and livestock). IPF is recognized on high-resolution computed tomography by peripheral, subpleural lower lobe reticular opacities in association with subpleural honeycomb changes. IPF is associated with a pathological lesion known as usual interstitial pneumonia (UIP). The UIP pattern consists of normal lung alternating with patches of dense fibrosis, taking the form of collagen sheets. The diagnosis of IPF requires correlation of the clinical setting with radiographic images and a lung biopsy. In the absence of lung biopsy, the diagnosis of IPF can be made by defined clinical criteria that were published in guidelines endorsed by several professional societies. Differential diagnosis includes other idiopathic interstitial pneumonia, connective tissue diseases (systemic sclerosis, polymyositis, rheumatoid arthritis), forme fruste of autoimmune disorders, chronic hypersensitivity pneumonitis and other environmental (sometimes occupational) exposures. IPF is typically progressive and leads to significant disability. The median survival is 2 to 5 years from the time of diagnosis. Medical therapy is ineffective in the treatment of IPF. New molecular therapeutic targets have been identified and several clinical trials are investigating the efficacy of novel medication. Meanwhile, pulmonary transplantation remains a viable option for patients with IPF. It is expected that, during the next decade, considerable progress will be made toward the understanding and treatment of this devastating illness
Contraindications of sentinel lymph node biopsy: Áre there any really?
BACKGROUND: One of the most exciting and talked about new surgical techniques in breast cancer surgery is the sentinel lymph node biopsy. It is an alternative procedure to standard axillary lymph node dissection, which makes possible less invasive surgery and side effects for patients with early breast cancer that wouldn't benefit further from axillary lymph node clearance. Sentinel lymph node biopsy helps to accurately evaluate the status of the axilla and the extent of disease, but also determines appropriate adjuvant treatment and long-term follow-up. However, like all surgical procedures, the sentinel lymph node biopsy is not appropriate for each and every patient. METHODS: In this article we review the absolute and relative contraindications of the procedure in respect to clinically positive axilla, neoadjuvant therapy, tumor size, multicentric and multifocal disease, in situ carcinoma, pregnancy, age, body-mass index, allergies to dye and/or radio colloid and prior breast and/or axillary surgery. RESULTS: Certain conditions involving host factors and tumor biologic characteristics may have a negative impact on the success rate and accuracy of the procedure. The overall fraction of patients unsuitable or with multiple risk factors that may compromise the success of the sentinel lymph node biopsy, is very small. Nevertheless, these patients need to be successfully identified, appropriately advised and cautioned, and so do the surgeons that perform the procedure. CONCLUSION: When performed by an experienced multi-disciplinary team, the SLNB is a highly effective and accurate alternative to standard level I and II axillary clearance in the vast majority of patients with early breast cancer
