37 research outputs found
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Achieving womenâs equity in academic medicine: challenging the standards
Platelet activation in the postoperative period after lung transplantation
Objective
During lung transplantation, cells in the pulmonary parenchyma are subjected to ischemia, hypothermic storage, and reperfusion injury. Platelets, whose granular contents include adhesion receptors, chemokines, and coactivating substances that activate inflammatory and coagulant cascades, likely play a critical role in the lung allograft response to ischemia and reperfusion. The platelet response to the pulmonary allograft, however, has never been studied. Here we report significant platelet activation immediately after lung transplantation.
Methods
We performed a prospective cohort study comparing markers of platelet activation in patients undergoing lung transplantation and patients undergoing nontransplant thoracotomy. Plasma levels of soluble P-selectin, soluble CD40 ligand, and plateletâleukocyte conjugates were measured before surgery, after skin closure, and at 6 postoperative hours.
Results
Both soluble P-selectin and soluble CD40 ligand levels increased significantly after lung transplantation but not after thoracotomy. Additionally, plateletâmonocyte conjugate fluorescence was significantly higher after lung transplantation than after thoracotomy alone.
Conclusion
These findings suggest that platelet activation is significantly increased after lung transplantation beyond that expected from the postoperative state. The increase in circulating plateletâmonocyte conjugates suggests an important interaction between platelets and inflammatory cells. Further research should examine whether platelet activation affects early graft function after lung transplantation
Increased Matrix Metalloproteinase (MMPs) Levels Do Not Predict Disease Severity or Progression in Emphysema
Rationale: Though matrix metalloproteinases (MMPs) are critical in the pathogenesis of COPD, their utility as a disease biomarker remains uncertain. This study aimed to determine whether bronchoalveolar lavage (BALF) or plasma MMP measurements correlated with disease severity or functional decline in emphysema. Methods: Enzyme-linked immunosorbent assay and luminex assays measured MMP-1, -9, -12 and tissue inhibitor of matrix metalloproteinase-1 in the BALF and plasma of non-smokers, smokers with normal lung function and moderate-to-severe emphysema subjects. In the cohort of 101 emphysema subjects correlative analyses were done to determine if MMP or TIMP-1 levels were associated with key disease parameters or change in lung function over an 18-month time period. Main Results: Compared to non-smoking controls, MMP and TIMP-1 BALF levels were significantly elevated in the emphysema cohort. Though MMP-1 was elevated in both the normal smoker and emphysema groups, collagenase activity was only increased in the emphysema subjects. In contrast to BALF, plasma MMP-9 and TIMP-1 levels were actually decreased in the emphysema cohort compared to the control groups. Both in the BALF and plasma, MMP and TIMP-1 measurements in the emphysema subjects did not correlate with important disease parameters and were not predictive of subsequent functional decline. Conclusions: MMPs are altered in the BALF and plasma of emphysema; however, the changes in MMPs correlate poorly with parameters of disease intensity or progression. Though MMPs are pivotal in the pathogenesis of COPD, these findings suggest that measuring MMPs will have limited utility as a prognostic marker in this disease. © 2013 D'Armiento et al
Nonmalignant Respiratory Effects of Chronic Arsenic Exposure from Drinking Water among Never-Smokers in Bangladesh
BACKGROUND: Arsenic from drinking water has been associated with malignant and nonmalignant respiratory illnesses. The association with nonmalignant respiratory illnesses has not been well established because the assessments of respiratory symptoms may be influenced by recall bias or interviewer bias because participants had visible skin lesions.
OBJECTIVES: We examined the relationship of the serum level of Clara cell protein CC 16-a novel biomarker for respiratory illnesses-with well As, total urinary As, and urinary As methylation indices.
METHODS: We conducted a cross-sectional study in nonsmoking individuals (n = 241) selected from a large cohort with a wide range of As exposure (0.1-761 mu g/L) from drinking water in Bangladesh. Total urinary As, urinary As metabolites, and serum CC16 were measured in urine and serum samples collected at baseline of the parent cohort study.
RESULTS: We observed an inverse association between urinary As and serum CC 16 among persons with skin lesions (beta = -0. 13, p = 0.01). We also observed a positive association between secondary methylation index in urinary As and CC16 levels (beta = 0. 12,,P = 0.05) in the overall study population; the association was stronger among people without skin lesions (beta = 0. 18, p = 0.04), indicating that increased methylation capability may be protective against As-induced respiratory damage. In a subsample of study participants undergoing spirometric measures (n = 3 1), we observed inverse associations between urinary As and predictive FEV1 (forced expiratory volume measured in 1 sec) (r = -0.37; FEV1/forced vital capacity ratio and primary methylation index (r = -0.42, p = 0.01).
CONCLUSIONS: The findings suggest that serum CC 16 may be a useful biomarker of epithelial lung damage in individuals with arsenical skin lesions. Also, we observed the deleterious respiratory effects of As exposure at concentrations lower than reported in earlier studies
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Mitochondrial iron chelation ameliorates cigarette-smoke induced bronchitis and emphysema in mice
Chronic obstructive pulmonary disease (COPD) is linked to both cigarette smoking and genetic determinants. We have previously identified iron-responsive element binding protein 2 (IRP2) as an important COPD susceptibility gene, with IRP2 protein increased in the lungs of individuals with COPD. Here we demonstrate that mice deficient in Irp2 were protected from cigarette smoke (CS)-induced experimental COPD. By integrating RIP-Seq, RNA-Seq, gene expression and functional enrichment clustering analysis, we identified IRP2 as a regulator of mitochondrial function in the lung. IRP2 increased mitochondrial iron loading and cytochrome c oxidase (COX), which led to mitochondrial dysfunction and subsequent experimental COPD. Frataxin-deficient mice with higher mitochondrial iron loading had impaired airway mucociliary clearance (MCC) and higher pulmonary inflammation at baseline, whereas synthesis of cytochrome c oxidase (Sco2)-deficient mice with reduced COX were protected from CS-induced pulmonary inflammation and impairment of MCC. Mice treated with a mitochondrial iron chelator or mice fed a low-iron diet were protected from CS-induced COPD. Mitochondrial iron chelation also alleviated CS-impairment of MCC, CS-induced pulmonary inflammation and CS-associated lung injury in mice with established COPD, suggesting a critical functional role and potential therapeutic intervention for the mitochondrial-iron axis in COPD
Effectiveness-based guidelines for the prevention of cardiovascular disease in women-2011 update: A Guideline from the American Heart Association
"Substantial progress has been made in the awareness, treatment, and prevention of cardiovascular disease (CVD) in women since the first women-specific clinical recommendations for the prevention of CVD were published by the American Heart Association (AHA) in 1999.1 The myth that heart disease is a âman's diseaseâ has been debunked; the rate of public awareness of CVD as the leading cause of death among US women has increased from 30% in 1997 to 54% in 2009.2 The age-adjusted death rate resulting from coronary heart disease (CHD) in females, which accounts for about half of all CVD deaths in women, was 95.7 per 100 000 females in 2007, a third of what it was in 1980.3,4 Approximately 50% of this decline in CHD deaths has been attributed to reducing major risk factors and the other half to treatment of CHD including secondary preventive therapies.4 Major randomized controlled clinical trials such as the Women's Health Initiative have changed the practice of CVD prevention in women over the past decade.5 The investment in combating this major public health issue for women has been significant, as have the scientific and medical achievements. Despite the gains that have been made, considerable challenges remain. In 2007, CVD still caused â1 death per minute among women in the United States.6 These represent 421 918 deaths, more women's lives than were claimed by cancer, chronic lower respiratory disease, Alzheimer disease, and accidents combined.6 Reversing a trend of the past 4 decades, CHD death rates in US women 35 to 54 years of age now actually appear to be increasing, likely because of the effects of the obesity epidemic.4 CVD rates in the United States are significantly higher for black females compared with their white counterparts (286.1/100 000 versus 205.7/100 000). This disparity parallels the substantially lower rate of awareness of heart disease and stroke that has been documented among black versus white women.2,6â8 Of concern is that in a recent AHA national survey, only 53% of women said the first thing they would do if they thought they were having a heart attack was to call 9-1-1. This distressing lack of appreciation by many women for the need for emergency care for acute cardiovascular events is a barrier to optimal survival among women and underscores the need for educational campaigns targeted to women.2