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1.
Am J Clin Oncol ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38764405

RESUMO

OBJECTIVES: Studies investigating preoperative 5-fraction radiation therapy (RT) for soft tissue sarcoma (STS) are limited. We performed a meta-analysis to determine the efficacy and safety of this treatment paradigm. METHODS: This study-level meta-analysis was conducted using Bayesian methods. Statistical estimation for risk of outcome rates was conducted by posterior mean and 95% highest posterior density (HPD) intervals. Studies with 2-year local control (LC) and description of major wound complications (MWC) per the CAN-NCIC-SR2 study were included and served as the primary endpoints. Secondary endpoints included rates of acute and late toxicity. A total of 10 studies were identified and 7 met the inclusion criteria. Subgroup analyses were performed for ≥30 Gy vs <30 Gy. RESULTS: A total of 209 patients from 7 studies were included. Five studies used ≥30 Gy (n=144), and 2 studies <30 Gy (n=64). Median follow-up was 29 months (range: 21 to 57 mo). Primary tumor location was lower extremity in 68% and upper extremity in 22%. Most tumors were intermediate or high grade (95%, 160/169), and 50% (79/158) were >10 cm. The two-year LC for the entire cohort was 96.9%, and the rate of MWC was 30.6%. There was a trend toward improved LC with ≥ 30 Gy (95% HPD: 0.95 to 0.99 vs 0.84 to 0.99). There was no difference in MWC (95% HPD: 0.18 to 0.42 vs 0.17 to 0.55) or late toxicity between the groups. CONCLUSION: Preoperative 5-fraction RT for STS demonstrates excellent 2-year LC with MWC and toxicity similar to standard fractionation preoperative RT. Multi-institutional trials with a universal RT protocol are warranted.

3.
ERJ Open Res ; 9(6)2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38020564

RESUMO

Background: Current guidelines on the management of chronic cough do not provide recommendations for the operation of specialist cough clinics. The objective of the present study was to develop expert consensus on goals and standard procedures for specialist cough clinics. Methods: We undertook a modified Delphi process, whereby initial statements proposed by experts were categorised and presented back to panellists over two ranking rounds using an 11-point Likert scale to identify consensus. Results: An international panel of 57 experts from 19 countries participated, with consensus reached on 15 out of 16 statements, covering the aims, roles and standard procedures of specialist cough clinics. Panellists agreed that specialist cough clinics offer optimal care for patients with chronic cough. They also agreed that history taking should enquire as to cough triggers, cough severity rating scales should be routinely used, and a minimum of chest radiography, spirometry and measurements of type 2 inflammatory markers should be undertaken in newly referred patients. The importance of specialist cough clinics in promoting clinical research and cough specialty training was acknowledged. Variability in healthcare resources and clinical needs between geographical regions was noted. Conclusions: The Delphi exercise provides a platform and guidance for both established cough clinics and those in planning stages.

5.
JCO Oncol Pract ; 18(11): e1866-e1873, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36206501

RESUMO

PURPOSE: The purpose of this study was to assess prostate-specific antigen (PSA) testing rates in persons experiencing homelessness (PEH), identify factors associated with screening, and compare PSA screening rates in PEH with a matched cohort of persons not experiencing homelessness (non-PEH). MATERIALS AND METHODS: We identified 9,249 potentially eligible PEH cared for at a large metropolitan hospital system from an institutional registry of all patients who presented to the health care system as homeless from 2014 to 2021. Homelessness was defined by the presence of the Z-code for homelessness (Z59), the listed address matching to the address of a homeless shelter or other transitional housing or a positive screen for homelessness. A matched cohort of 10,000 non-PEH was generated for comparison. Univariate chi-square analysis and multivariate logistic regression were performed to evaluate variables associated with PSA testing. RESULTS: A total of 1,605 PEH and 3,413 non-PEH were eligible for PSA screening within the study timeframe. Half of PEH were Black (50%). Medicaid was the most common insurance (51%), followed by Medicare (18%). PEH were less likely to have a PCP (58% v 81%, P < .001) and had a significantly lower PSA testing rate (13% v 34%, P < .001) compared with non-PEH. Univariate analysis revealed that PSA testing was more common in PEH who were employed (P < .001), had private insurance or Medicare (P < .001), or had an established primary care provider (PCP; P < .001). Multivariate analysis confirmed that having a PCP (OR, 2.54; 95% CI, 1.62 to 4.00; P < .001) significantly increased the likelihood of PSA testing in PEH. CONCLUSION: PEH experience low rates of prostate cancer screening. Interventions to increase screening in this population, including increased PCP access, are needed.


Assuntos
Pessoas Mal Alojadas , Neoplasias da Próstata , Masculino , Humanos , Idoso , Estados Unidos , Detecção Precoce de Câncer , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/epidemiologia , Medicare
6.
Cureus ; 13(9): e18176, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34703701

RESUMO

INTRODUCTION: Publishing research is an important component of medical students' career development and becoming a more competitive residency applicant. Many medical schools offer structured programs to enable students to participate in research during their preclinical and clinical years, but the majority of student-mentor partnerships do not culminate in publication across a variety of institutions and medical specialties. The primary objective of this study is to determine if any factors associated with mentee-mentor partnerships are predictive of publication from two school-sponsored research programs at a single US medical school. METHODS: The PubMed-indexed publications of all student-mentor pairings from a summer internship (after year 1 of medical school) or research elective (during year 4 of medical school) at a single institution from 2008 to 2018 were retrospectively reviewed. Student/mentor demographic information was associated with the probability of publication. RESULTS: A total of 124 students participated in the summer internship with 32 (26%) achieving publication. The publication was significantly more likely for students that were from highly ranked undergraduate institutions (p = 0.04; likelihood ratio (LR) = 5.788), were future Alpha Omega Alpha (AOA) members (p = 0.03; LR = 4.597), or worked with a mentor focused on clinical rather than basic science research (p = 0.02; LR = 5.662). Forty-four students participated in the fourth-year elective with 11 (25%) achieving publication. The publication was more likely if the student worked with a mentor without a Doctor of Medicine (MD)/Doctor of Osteopathic Medicine (DO) degree (p = 0.001; LR = 7.051), with a PhD degree (p = 0.002; LR = 7.820), or a mentor with prior publication(s) with prior mentee(s) (p = 0.03; LR = 5.368). CONCLUSION: Only one-quarter of mentor-mentee research pairings resulted in publication, with student-related factors more predictive for publication from the internship and mentor-related factors more predictive of publication from the elective. Approaches to promote successful completion of medical student research projects should be considered to yield the greatest value from students' work and strengthen the development of future physician-scientists.

7.
ERJ Open Res ; 7(3)2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34350286

RESUMO

OBJECTIVE: Airway sensory nerves involved in the cough reflex are activated by adenosine triphosphate (ATP) agonism of P2X purinoceptor 3 (P2X3) receptors. Transient receptor potential vanilloid 4 (TRPV4) channel activation causes ATP release from airway cells, and it is hypothesised that a TRPV4-ATP-P2X3 axis contributes to chronic cough. An adaptive study was run to determine if TRPV4 inhibition, using the selective TRPV4 channel blocker GSK2798745, was effective in reducing cough. METHODS: A two-period randomised, double blinded, placebo-controlled crossover study was designed with interim analyses for futility and sample size adjustment. Refractory chronic cough patients received either GSK2798745 or placebo once daily for 7 days with a washout between treatments. Pharmacokinetic samples were collected for analysis of GSK2798745 at end of study. The primary end-point was total cough counts assessed objectively during day-time hours (10 h) following 7 days of dosing. RESULTS: Interim analysis was performed after 12 participants completed both treatment periods. This showed a 32% increase in cough counts on Day 7 for GSK2798745 compared to placebo; the pre-defined negative criteria for the study were met and the study was stopped. At this point 17 participants had been enrolled (mean 61 years; 88% female), and 15 had completed the study. Final study results for posterior median cough counts showed a 34% (90% credible interval: -3%, +85%) numerical increase for GSK2798745 compared to placebo. CONCLUSION: There was no evidence of an anti-tussive effect of GSK2798745. The study design allowed the decision on lack of efficacy to be made with minimal participant exposure to the investigational drug.

8.
Eur Respir J ; 58(5)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33986030

RESUMO

BACKGROUND: ATP acting via P2X3 receptors is an important mediator of refractory chronic cough (RCC). This phase 2a double-blinded crossover study assessed the safety, tolerability and efficacy of eliapixant (BAY 1817080), a selective P2X3 receptor antagonist, in adults with RCC attending specialist centres. METHODS: In period A, patients received placebo for 2 weeks then eliapixant 10 mg for 1 week. In period B, patients received eliapixant 50, 200 and 750 mg twice daily for 1 week per dose level. Patients were randomised 1:1 to period A-B (n=20) or B-A (n=20). The primary efficacy end-point was change in cough frequency assessed over 24 h. The primary safety end-point was frequency and severity of adverse events (AEs). RESULTS: 37 patients completed randomised therapy. Mean cough frequency fell by 17.4% versus baseline with placebo. Eliapixant reduced cough frequency at doses ≥50 mg (reduction versus placebo at 750 mg: 25% (90% CI 11.5-36.5%); p=0.002). Doses ≥50 mg also significantly reduced cough severity. AEs, mostly mild or moderate, were reported in 65% of patients with placebo and 41-49% receiving eliapixant. Cumulative rates of taste-related AEs were 3% with placebo and 5-21% with eliapixant; all were mild. CONCLUSIONS: Selective P2X3 antagonism with eliapixant significantly reduced cough frequency and severity, confirming this as a viable therapeutic pathway for RCC. Taste-related side-effects were lower at therapeutic doses than with the less selective P2X3 antagonist gefapixant. Selective P2X3 antagonism appears to be a novel therapeutic approach for RCC.


Assuntos
Tosse , Antagonistas do Receptor Purinérgico P2X , Adulto , Doença Crônica , Tosse/tratamento farmacológico , Estudos Cross-Over , Método Duplo-Cego , Humanos , Receptores Purinérgicos P2X3 , Resultado do Tratamento
9.
ERJ Open Res ; 6(1)2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32201684

RESUMO

Nonpharmacological cough control therapy (CCT) is effective for refractory chronic cough but there is a significant subgroup of nonresponders. CCT appears to be effective in cough associated with underlying disease such as asthma. http://bit.ly/2uCCwu3.

10.
Ann Palliat Med ; 8(4): 516-522, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31594377

RESUMO

Radiation therapy (RT) can effectively palliate a variety of symptoms in patients with metastatic cancer, using relatively low doses that infrequently cause major side effects. However, palliative radiation is often underutilized and sub-optimally implemented. In this study, we surveyed the Society of Palliative Radiation Oncology (SPRO) membership to identify barriers to appropriate referral for palliative RT that they encounter in their practice, and identify specific groups of physicians who radiation oncologists believed would benefit most from further education on when to refer patients. A total of 28 radiation oncologists responded to the survey with a response rate of 20.5%. On average, participants felt that referrals for palliative RT were inappropriately delayed 46.5% [standard deviation (STD) 20.2%] of the time. The most common barrier to referral for medical oncologists was thought to be potential interference with systemic therapy (33%); for primary care physicians and surgeons it was a lack of knowledge about the benefit (42%), and for palliative care physicians it was concern for patient convenience (25%). For brain metastases and spinal cord compression radiation oncology was felt to be part of the initial referral sequence more than 50% of the time, but less so for thoracic airway obstruction/bleeding (38%), esophageal obstruction (16%), or urinary obstruction/bleeding (8%), where another subspecialist was more often consulted first. Primary care, geriatric medicine, and emergency medicine were considered among the least knowledgeable specialties about palliative radiation. These hypothesis-generating findings can guide approaches to improve referral patterns for this important aspect of supportive care.


Assuntos
Neoplasias/radioterapia , Cuidados Paliativos/métodos , Radioterapia (Especialidade)/estatística & dados numéricos , Encaminhamento e Consulta/normas , Utilização de Instalações e Serviços , Humanos , Avaliação das Necessidades , Padrões de Prática Médica , Radio-Oncologistas/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos
11.
J Health Psychol ; 24(6): 707-716, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-28810370

RESUMO

Chronic refractory cough patients have persistent, unexplained, treatment-resistant symptoms. Very little is known about non-physiological processes underlying chronic refractory cough or patients' experience of the condition. In all, 14 patients participated in semi-structured interviews. Interviews were based on the comprehensive cognitive behavioural model and analysed thematically. Eight key themes emerged illustrating that the experience of the onset and persistence of chronic refractory cough is complex, often involving multiple interlinking factors. Themes highlighted the involvement of biological and psychological factors, and the prominent role of the social dimension in how the cough is experienced, perceived and managed. Implications for intervention development are discussed.


Assuntos
Doença Crônica/psicologia , Tosse/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa
12.
Pract Radiat Oncol ; 9(1): e90-e97, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30267899

RESUMO

PURPOSE: Stereotactic body radiation therapy (SBRT) is commonly used to treat primary or oligometastatic malignancies in the lung, but most of the available data that describe the safety and efficacy of SBRT are for smaller tumors. The purpose of this study was to evaluate the impact of tumor size, among other factors, on local control (LC) and radiation pneumonitis (RP) in patients who received lung SBRT. METHODS AND MATERIALS: This retrospective study included 144 patients with 100 primary (57.1%) and 75 metastatic (42.9%) lung tumors treated with SBRT between 2012 and 2018. Measurements of tumor size, treatment volume, histology, and radiation dose were evaluated for association with LC. Additional factors evaluated for association with the development of symptomatic RP included volume of the lung, heart, and central airway exposed to relevant doses of radiation. RESULTS: The median follow-up time was 15.0 months (interquartile range, 8.0-26.0 months). LC rates at 12 and 24 months posttreatment were 95.1% and 92.7%, respectively. LC at 1 year was higher for tumors <5 cm in diameter than for tumors >5 cm in diameter (98.2% vs 79.8%, respectively; P < .01). On univariate analysis, LC was associated with a smaller gross tumor volume (GTV) diameter (P < .01), GTV volume (P < .01), planning target volume (PTV) diameter (P < .01), PTV volume (P < .01), and larger PTV-to-GTV ratio (P = .04). Tumor histology and treatment intent were not correlated with LC. RP was associated with a higher ipsilateral lung mean lung dose (P = .02), V2.5 (P = .03), V5 (P = .02), V13 (P = .03), V20 (P = .05), V30 (P = .02), V40 (P = .02), and V50 (P = .03), and several similar total lung dose parameters and heart maximum point dose (P = .02). The optimal mean ipsilateral lung dose cutoff predictive of RP was 8.6 Gy. CONCLUSIONS: A larger tumor size and smaller PTV-to-GTV ratio was associated with local recurrence of lung tumors treated with SBRT, but ipsilateral lung doses were most associated with symptomatic RP.


Assuntos
Adenocarcinoma/secundário , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma de Células Escamosas/secundário , Neoplasias Pulmonares/patologia , Recidiva Local de Neoplasia/diagnóstico , Pneumonite por Radiação/etiologia , Radiocirurgia/efeitos adversos , Adenocarcinoma/cirurgia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma de Células Escamosas/cirurgia , Feminino , Seguimentos , Humanos , Incidência , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/etiologia , Prognóstico , Dosagem Radioterapêutica , Estudos Retrospectivos , Taxa de Sobrevida
13.
Adv Radiat Oncol ; 3(3): 399-404, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30202808

RESUMO

PURPOSE: Radiation therapy (RT) and nivolumab are standard therapies for a wide range of advanced and metastatic cancers, yet little is known about the toxicity profile of their combined treatment. The rate of grade ≥3 toxicities from nivolumab monotherapy and radiation-only palliative treatments has been reported at 10% to 18% and 0% to 26%, respectively. We reviewed our experience to assess the acute toxicity profile of concurrent RT-nivolumab. METHODS AND MATERIALS: A retrospective review of all consecutive patients from January 2015 to May 2017 who received concurrent RT-nivolumab was conducted at 4 separate centers. Concurrent RT-nivolumab was defined as RT completed between 3 days prior to initial nivolumab infusion and 28 days after the last nivolumab infusion. RESULTS: Of the 261 patients who received nivolumab, 46 (17.6%) had concurrent RT to 67 treatment sites. The median follow-up was 3.3 months (interquartile range, 1.7-6.1 months) and the 1-year overall survival rate was 22%. For the 11 of 46 patients (24%) who were alive at last analysis, the median follow-up was 12.8 months (interquartile range, 8.3-14.9 months). The most common histology, RT prescription, and treatment site were non-small cell lung cancer (23 of 46 patients; 50%), 30 Gy in 10 fractions (24 of 67 patients; 35.8%), and abdomen/pelvis (16 of 67 patients; 24%), respectively. Four patients with melanoma had concurrent ipilimumab and were removed from the final toxicity analysis of RT-nivolumab. Within 3 months of treatment with RT-nivolumab, 4 of 42 patients (9.5%) experienced grade 3 toxicity and 2 of these patients' toxicities were attributed specifically to the addition of RT: grade 3 hearing loss after whole brain RT and grade 3 pancreatitis after stereotactic body RT to the left adrenal gland. One death from transaminitis was attributed to nivolumab alone because the RT field did not encompass the liver. CONCLUSIONS: Concurrent RT-nivolumab did not appear to increase the toxicity profile from the previously reported toxicity rates from nivolumab or radiation alone.

14.
ERJ Open Res ; 3(1)2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28344979

RESUMO

Chronic refractory cough (CRC) is a common problem in respiratory clinics. Adverse effects on quality of life are documented in the literature, but relatively little is known about the underlying psychological factors in this patient population. We aimed to investigate the association of psychological factors with chronic cough, comparing CRC to explained cough and non-cough groups. 67 patients attending a specialist cough clinic (CRC, n=25; explained cough, n=42) and 22 non-cough individuals participated. All participants completed the Hospital Anxiety & Depression Scale, Big Five Inventory (Personality), Chalder Fatigue Scale and Patient Health Questionnaire-15. Cough patients also completed the Illness Perception Questionnaire-Revised. Appropriate statistical analyses were used to compare participant groups. Chronic refractory coughers displayed significantly higher levels of anxiety, depression, fatigue and somatic physical symptoms than non-cough participants. Compared to explained coughers, there were higher depression and fatigue scores and significantly more negative illness representations (specifically, strong beliefs regarding negative consequences, lower illness coherence and higher emotional representations). "Explained" coughers reported significantly increased fatigue and somatic symptoms in comparison to non-coughers. The prevalence of fatigue, low mood, negative illness beliefs and increased physical symptom reporting should be considered in consultations and in developing novel interventions for CRC patients.

15.
Thorax ; 72(2): 129-136, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27682331

RESUMO

BACKGROUND: Physiotherapy, and speech and language therapy are emerging non-pharmacological treatments for refractory chronic cough. We aimed to investigate the efficacy of a physiotherapy, and speech and language therapy intervention (PSALTI) to improve health-related quality of life (HRQoL) and to reduce cough frequency in patients with refractory chronic cough. METHODS: In this multicentre randomised controlled trial, patients with refractory chronic cough were randomised to four weekly 1:1 sessions of either PSALTI consisting of education, laryngeal hygiene and hydration, cough suppression techniques, breathing exercises and psychoeducational counselling or control intervention consisting of healthy lifestyle advice. We assessed the change in HRQoL at week 4 with the Leicester Cough Questionnaire (LCQ). Secondary efficacy outcomes included 24-hour objective cough frequency (Leicester Cough Monitor) and cough reflex sensitivity. The primary analysis used an analysis of covariance adjusted for baseline measurements with the intention-to-treat population. This study was registered at UK Clinical Research Network (UKCRN ID 10678). FINDINGS: Between December 2011 and April 2014, we randomly assigned 75 participants who underwent baseline assessment (34 PSALTI and 41 controls). In the observed case analysis, HRQoL (LCQ) improved on average by 1.53 (95% CI 0.21 to 2.85) points more in PSALTI group than with control (p=0.024). Cough frequency decreased by 41% (95% CI 36% to 95%) in PSALTI group relative to control (p=0.030). The improvements within the PSALTI group were sustained up to 3 months. There was no significant difference between groups in the concentration of capsaicin causing five or more coughs. INTERPRETATION: Greater improvements in HRQoL and cough frequency were observed with PSALTI intervention. Our findings support the use of PSALTI for patients with refractory chronic cough. TRIAL REGISTRATION NUMBER: UKCRN ID 10678 and ISRCTN 73039760; Results.


Assuntos
Tosse/terapia , Terapia da Linguagem , Modalidades de Fisioterapia , Fonoterapia , Idoso , Doença Crônica , Aconselhamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Método Simples-Cego , Resultado do Tratamento
16.
Eur Respir J ; 44(5): 1149-55, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25186267

RESUMO

Reports from individual centres suggest a preponderance of females with chronic cough. Females also have heightened cough reflex sensitivity. Here we have reviewed the age and sex of unselected referrals to 11 cough clinics. To investigate the cause of any observed sex dimorphism, functional magnetic resonance imaging of putative cough centres was analysed in normal volunteers. The demographic profile of consecutive patients presenting with chronic cough was evaluated. Cough challenge with capsaicin was undertaken in normal volunteers to construct a concentration-response curve. Subsequent functional magnetic resonance imaging during repeated inhalation of sub-tussive concentrations of capsaicin observed areas of activation within the brain and differences in the sexes identified. Of the 10,032 patients presenting with chronic cough, two-thirds (6591) were female (mean age 55 years). The patient profile was largely uniform across centres. The most common age for presentation was 60-69 years. The maximum tolerable dose of inhaled capsaicin was lower in females; however, a significantly greater activation of the somatosensory cortex was observed. Patients presenting with chronic cough from diverse racial and geographic backgrounds have a strikingly homogeneous demographic profile, suggesting a distinct clinical entity. The preponderance of females may be explained by sex-related differences in the central processing of cough sensation.


Assuntos
Doença Crônica , Tosse/fisiopatologia , Fatores Sexuais , Administração por Inalação , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Capsaicina , Criança , Pré-Escolar , Feminino , Saúde Global , Voluntários Saudáveis , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Reflexo , Sistema de Registros , Estudos Retrospectivos , Distribuição por Sexo , Córtex Somatossensorial/fisiopatologia , Adulto Jovem
17.
Free Radic Biol Med ; 52(6): 1024-32, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22240154

RESUMO

Fibrotic remodelling of lung parenchymal and airway compartments is the major contributor to life-threatening organ dysfunction in chronic lung diseases such as idiopathic pulmonary fibrosis (IPF) and Chronic Obstructive Pulmonary Disease (COPD). Since transforming growth factor-ß1 (TGF-ß1) is believed to play a key role in disease pathogenesis and markers of oxidative stress are also commonly detected in bronchoalveolar lavage (BAL) from such patients we sought to investigate whether both factors might be interrelated. Here we investigated the hypothesis that oxidative stress to the lung epithelium promotes fibrotic repair by driving epithelial-to-mesenchymal transition (EMT) via the augmentation of TGF-ß1. We show that in response to 400µM hydrogen peroxide (H(2)O(2)) A549 cells, used a model for alveolar epithelium, and human primary bronchial epithelial cells (PBECs) undergo EMT displaying morphology changes, decreased expression of epithelial markers (E-cadherin and ZO-1), increased expression of mesenchymal markers (vimentin and α-smooth muscle actin) as well as increased secretion of extracelluar matrix components. The same oxidative stress also promotes expression of TGF-ß1. Inhibition of TGF-ß1 signalling as well as treatment with antioxidants such as phenyl tert-butylnitrone (PBN) and superoxide dismutase 3 (SOD3) prevent the oxidative stress driven EMT-like changes described above. Interventions also inhibited EMT-like changes. This study identifies a link between oxidative stress, TGF-ß1 and EMT in lung epithelium and highlights the potential for antioxidant therapies to limit EMT and its potential contribution to chronic lung disease.


Assuntos
Transição Epitelial-Mesenquimal , Fibrose Pulmonar Idiopática/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Mucosa Respiratória/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo , Remodelação das Vias Aéreas/efeitos dos fármacos , Antioxidantes/farmacologia , Biomarcadores/metabolismo , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Radicais Livres/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Fibrose Pulmonar Idiopática/patologia , Pulmão/patologia , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/patologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/farmacologia , Fator de Crescimento Transformador beta1/genética
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