RESUMO
BACKGROUND: Circulating biomarkers for lung damage are lacking. Lung epithelium-specific DNA methylation patterns can potentially report the presence of lung-derived cell-free DNA (cfDNA) in blood, as an indication of lung cell death. METHODS: We sorted human lung alveolar and bronchial epithelial cells from surgical specimens, and obtained their methylomes using whole-genome bisulfite sequencing. We developed a PCR sequencing assay determining the methylation status of 17 loci with lung-specific methylation patterns, and used it to assess lung-derived cfDNA in the plasma of healthy volunteers and patients with lung disease. RESULTS: Loci that are uniquely unmethylated in alveolar or bronchial epithelial cells are enriched for enhancers controlling lung-specific genes. Methylation markers extracted from these methylomes revealed that normal lung cell turnover probably releases cfDNA into the air spaces, rather than to blood. People with advanced lung cancer show a massive elevation of lung cfDNA concentration in blood. Among individuals undergoing bronchoscopy, lung-derived cfDNA is observed in the plasma of those later diagnosed with lung cancer, and to a lesser extent in those diagnosed with other lung diseases. Lung cfDNA is also elevated in patients with acute exacerbation of COPD compared with patients with stable disease, and is associated with future exacerbation and mortality in these patients. CONCLUSIONS: Universal cfDNA methylation markers of normal lung epithelium allow for mutation-independent, sensitive and specific detection of lung-derived cfDNA, reporting on ongoing lung injury. Such markers can find broad utility in the study of normal and pathologic human lung dynamics.
Assuntos
Ácidos Nucleicos Livres , Neoplasias Pulmonares , Humanos , Metilação de DNA , Ácidos Nucleicos Livres/genética , Biópsia Líquida , Biomarcadores , Epitélio , Pulmão , Neoplasias Pulmonares/genética , Biomarcadores Tumorais/genéticaRESUMO
BACKGROUND: Chronic obstructive pulmonary disease(COPD) is a common and debilitating condition, often accompanied by other co-morbidities. The Hadassah Medical Center'smulti-disciplinary approach in treating COPD patients in a one-stop shopfor COPD patients is the first of its kind in Israel. It includes pulmonary physicians, a nurse coordinator, dietitian, psychotherapist, physiotherapist, and a smoking cessation program. OBJECTIVES: To characterize efficacy of such a program in COPD patients. METHODS: Demographic and clinical data from patients referred to the Hadassah COPD center, including co-morbidities, baseline symptoms (using the CAT questioner), spirometry results, 6-minute walking distance (6MWD) test and current treatment were collected and compared to the same data after 6-12 months of treatment. RESULTS: Some 154 patients were evaluated; mean age 64 years; 67% male; 53% current smokers. Only 74% received chronic treatment for COPD. Average body mass index was 28, CAT score 21.3, and mean FEV1 was 1.38 liters (53% of predicted).The mean exacerbation rate during the year prior to referral was 1.72 with a 1.07 annual admission rate. Following treatment, a small increase was noted in FEV1 to 1.47 liters, 54.4% of predicted; improvement in CAT scores to 16.5 with improvement seen in 70% of patients, and a 42 meter increase in the 6MWD (from 344 to 386 meters) with some improvement of effort capacity in 77% of patients. The rate of smokers decreased to 21%, and 97% of patients received medical treatment for COPD. CONCLUSIONS: Multidisciplinary approach is feasible and efficacious in patients with COPD.
Assuntos
Equipe de Assistência ao Paciente , Doença Pulmonar Obstrutiva Crônica/terapia , Feminino , Humanos , Comunicação Interdisciplinar , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Espirometria , Inquéritos e Questionários , Resultado do TratamentoRESUMO
BACKGROUND: Although massive bleeding following transbronchial lung biopsies (TBLB) is rare, even minor hemorrhage may prolong the procedure and result in inadequate sampling. Tranexamic acid (TXA) is an antifibrinolytic agent, which reduces bleeding in numerous scenarios, however, its prophylactic use in mitigating post-TBLB bleeding has not been investigated. We conducted a prospective, randomized, double-blind, placebo-controlled trial to determine whether topical infusion of TXA prior to TBLB would reduce bleeding, shorten procedure duration and increase the number of biopsies obtained. METHODS: We blindly randomized patients undergoing TBLB to receive topical TXA or placebo in the lobar bronchus prior to biopsies. Vital signs, procedure length, fluid balance (as a measure of the amount of bleeding), operator's assessment of bleeding, and number of biopsies obtained were measured. Data was analyzed using the two-tailed Student's T-Test, Chi-square or Mann-Whitney tests as appropriate. RESULTS: Fifty patients were randomized, 26 to the TXA arm. The bleeding in the TXA group was significantly lower (P = 0.0037), with more specimens being obtained (placebo 7 (6, 9) (median and interquartile range) vs. TXA 9 (8, 10), P = 0.023) and no difference in procedure length (placebo 30 min (29.3, 34.3) vs. TXA 30 (24.8, 36), P = 0.90). There were no clinically significant adverse events in any of the groups up to one month of follow up. CONCLUSION: Endobronchial installation of TXA prior to obtaining TBLB results in less bleeding and allows more biopsies to be obtained with no additional adverse events. The prophylactic use of TXA during TBLB may be considered as standard.